# Minimal valid case: an empty histogram.
load 5m
	empty_histogram	{{}}

eval instant at 1m empty_histogram
	{__name__="empty_histogram"} {{}}

eval instant at 1m histogram_count(empty_histogram)
	{} 0

eval instant at 1m histogram_sum(empty_histogram)
	{} 0

eval instant at 1m histogram_avg(empty_histogram)
	{} NaN

eval instant at 1m histogram_fraction(-Inf, +Inf, empty_histogram)
	{} NaN

eval instant at 1m histogram_fraction(0, 8, empty_histogram)
	{} NaN

clear

# buckets:[1 2 1] means 1 observation in the 1st bucket, 2 observations in the 2nd and 1 observation in the 3rd (total 4).
load 5m
	single_histogram	{{schema:0 sum:5 count:4 buckets:[1 2 1]}}

# histogram_count extracts the count property from the histogram.
eval instant at 1m histogram_count(single_histogram)
	{} 4

# histogram_sum extracts the sum property from the histogram.
eval instant at 1m histogram_sum(single_histogram)
	{} 5

# histogram_avg calculates the average from sum and count properties.
eval instant at 1m histogram_avg(single_histogram)
	{} 1.25

# We expect half of the values to fall in the range 1 < x <= 2.
eval instant at 1m histogram_fraction(1, 2, single_histogram)
	{} 0.5

# We expect all values to fall in the range 0 < x <= 8.
eval instant at 1m histogram_fraction(0, 8, single_histogram)
	{} 1

# Median is 1.5 due to linear estimation of the midpoint of the middle bucket, whose values are within range 1 < x <= 2.
eval instant at 1m histogram_quantile(0.5, single_histogram)
	{} 1.5

clear

# Repeat the same histogram 10 times.
load 5m
	multi_histogram	{{schema:0 sum:5 count:4 buckets:[1 2 1]}}x10

eval instant at 5m histogram_count(multi_histogram)
	{} 4

eval instant at 5m histogram_sum(multi_histogram)
	{} 5

eval instant at 5m histogram_avg(multi_histogram)
	{} 1.25

eval instant at 5m histogram_fraction(1, 2, multi_histogram)
	{} 0.5

eval instant at 5m histogram_quantile(0.5, multi_histogram)
	{} 1.5


# Each entry should look the same as the first.
eval instant at 50m histogram_count(multi_histogram)
	{} 4

eval instant at 50m histogram_sum(multi_histogram)
	{} 5

eval instant at 50m histogram_avg(multi_histogram)
	{} 1.25

eval instant at 50m histogram_fraction(1, 2, multi_histogram)
	{} 0.5

eval instant at 50m histogram_quantile(0.5, multi_histogram)
	{} 1.5

clear

# Accumulate the histogram addition for 10 iterations, offset is a bucket position where offset:0 is always the bucket
# with an upper limit of 1 and offset:1 is the bucket which follows to the right. Negative offsets represent bucket
# positions for upper limits <1 (tending toward zero), where offset:-1 is the bucket to the left of offset:0.
load 5m
	incr_histogram	{{schema:0 sum:4 count:4 buckets:[1 2 1]}}+{{sum:2 count:1 buckets:[1] offset:1}}x10

eval instant at 5m histogram_count(incr_histogram)
	{} 5

eval instant at 5m histogram_sum(incr_histogram)
	{} 6

eval instant at 5m histogram_avg(incr_histogram)
	{} 1.2

# We expect 3/5ths of the values to fall in the range 1 < x <= 2.
eval instant at 5m histogram_fraction(1, 2, incr_histogram)
	{} 0.6

eval instant at 5m histogram_quantile(0.5, incr_histogram)
	{} 1.5


eval instant at 50m incr_histogram
	{__name__="incr_histogram"} {{count:14 sum:24 buckets:[1 12 1]}}

eval instant at 50m histogram_count(incr_histogram)
	{} 14

eval instant at 50m histogram_sum(incr_histogram)
	{} 24

eval instant at 50m histogram_avg(incr_histogram)
    {} 1.7142857142857142

# We expect 12/14ths of the values to fall in the range 1 < x <= 2.
eval instant at 50m histogram_fraction(1, 2, incr_histogram)
	{} 0.8571428571428571

eval instant at 50m histogram_quantile(0.5, incr_histogram)
	{} 1.5

# Per-second average rate of increase should be 1/(5*60) for count and buckets, then 2/(5*60) for sum.
eval instant at 50m rate(incr_histogram[10m])
    {} {{count:0.0033333333333333335 sum:0.006666666666666667 offset:1 buckets:[0.0033333333333333335]}}

# Calculate the 50th percentile of observations over the last 10m.
eval instant at 50m histogram_quantile(0.5, rate(incr_histogram[10m]))
	{} 1.5

clear

# Schema represents the histogram resolution, different schema have compatible bucket boundaries, e.g.:
#  0: 1 2 4 8 16 32 64 (higher resolution)
# -1: 1   4   16    64  (lower resolution)
#
# Histograms can be merged as long as the histogram to the right is same resolution or higher.
load 5m
	low_res_histogram	{{schema:-1 sum:4 count:1 buckets:[1] offset:1}}+{{schema:0 sum:4 count:4 buckets:[2 2] offset:1}}x1

eval instant at 5m low_res_histogram
	{__name__="low_res_histogram"} {{schema:-1 count:5 sum:8 offset:1 buckets:[5]}}

eval instant at 5m histogram_count(low_res_histogram)
	{} 5

eval instant at 5m histogram_sum(low_res_histogram)
	{} 8

eval instant at 5m histogram_avg(low_res_histogram)
	{} 1.6

# We expect all values to fall into the lower-resolution bucket with the range 1 < x <= 4.
eval instant at 5m histogram_fraction(1, 4, low_res_histogram)
	{} 1

clear

# z_bucket:1 means there is one observation in the zero bucket and z_bucket_w:0.5 means the zero bucket has the range
# 0 < x <= 0.5. Sum and count are expected to represent all observations in the histogram, including those in the zero bucket.
load 5m
	single_zero_histogram {{schema:0 z_bucket:1 z_bucket_w:0.5 sum:0.25 count:1}}

eval instant at 1m histogram_count(single_zero_histogram)
	{} 1

eval instant at 1m histogram_sum(single_zero_histogram)
	{} 0.25

eval instant at 1m histogram_avg(single_zero_histogram)
	{} 0.25

# When only the zero bucket is populated, or there are negative buckets, the distribution is assumed to be equally
# distributed around zero; i.e. that there are an equal number of positive and negative observations. Therefore the
# entire distribution must lie within the full range of the zero bucket, in this case: -0.5 < x <= +0.5.
eval instant at 1m histogram_fraction(-0.5, 0.5, single_zero_histogram)
	{} 1

# Half of the observations are estimated to be zero, as this is the midpoint between -0.5 and +0.5.
eval instant at 1m histogram_quantile(0.5, single_zero_histogram)
	{} 0

clear

# Let's turn single_histogram upside-down.
load 5m
	negative_histogram {{schema:0 sum:-5 count:4 n_buckets:[1 2 1]}}

eval instant at 1m histogram_count(negative_histogram)
	{} 4

eval instant at 1m histogram_sum(negative_histogram)
	{} -5

eval instant at 1m histogram_avg(negative_histogram)
	{} -1.25

# We expect half of the values to fall in the range -2 < x <= -1.
eval instant at 1m histogram_fraction(-2, -1, negative_histogram)
	{} 0.5

eval instant at 1m histogram_quantile(0.5, negative_histogram)
	{} -1.5

clear

# Two histogram samples.
load 5m
	two_samples_histogram {{schema:0 sum:4 count:4 buckets:[1 2 1]}} {{schema:0 sum:-4 count:4 n_buckets:[1 2 1]}}

# We expect to see the newest sample.
eval instant at 5m histogram_count(two_samples_histogram)
	{} 4

eval instant at 5m histogram_sum(two_samples_histogram)
	{} -4

eval instant at 5m histogram_avg(two_samples_histogram)
	{} -1

eval instant at 5m histogram_fraction(-2, -1, two_samples_histogram)
	{} 0.5

eval instant at 5m histogram_quantile(0.5, two_samples_histogram)
	{} -1.5

clear

# Add two histograms with negated data.
load 5m
	balanced_histogram {{schema:0 sum:4 count:4 buckets:[1 2 1]}}+{{schema:0 sum:-4 count:4 n_buckets:[1 2 1]}}x1

eval instant at 5m histogram_count(balanced_histogram)
	{} 8

eval instant at 5m histogram_sum(balanced_histogram)
	{} 0

eval instant at 5m histogram_avg(balanced_histogram)
	{} 0

eval instant at 5m histogram_fraction(0, 4, balanced_histogram)
	{} 0.5

# If the quantile happens to be located in a span of empty buckets, the actually returned value is the lower bound of
# the first populated bucket after the span of empty buckets.
eval instant at 5m histogram_quantile(0.5, balanced_histogram)
	{} 0.5

clear

# Add histogram to test sum(last_over_time) regression
load 5m
    incr_sum_histogram{number="1"} {{schema:0 sum:0 count:0 buckets:[1]}}+{{schema:0 sum:1 count:1 buckets:[1]}}x10
    incr_sum_histogram{number="2"} {{schema:0 sum:0 count:0 buckets:[1]}}+{{schema:0 sum:2 count:1 buckets:[1]}}x10

eval instant at 50m histogram_sum(sum(incr_sum_histogram))
    {} 30

eval instant at 50m histogram_sum(sum(last_over_time(incr_sum_histogram[5m])))
    {} 30

clear

# Apply rate function to histogram.
load 15s
    histogram_rate {{schema:1 count:12 sum:18.4 z_bucket:2 z_bucket_w:0.001 buckets:[1 2 0 1 1] n_buckets:[1 2 0 1 1]}}+{{schema:1 count:9 sum:18.4 z_bucket:1 z_bucket_w:0.001 buckets:[1 1 0 1 1] n_buckets:[1 1 0 1 1]}}x100

eval instant at 5m rate(histogram_rate[45s])
    {} {{schema:1 count:0.6 sum:1.2266666666666652 z_bucket:0.06666666666666667 z_bucket_w:0.001 buckets:[0.06666666666666667 0.06666666666666667 0 0.06666666666666667 0.06666666666666667] n_buckets:[0.06666666666666667 0.06666666666666667 0 0.06666666666666667 0.06666666666666667]}}

eval range from 5m to 5m30s step 30s rate(histogram_rate[45s])
    {} {{schema:1 count:0.6 sum:1.2266666666666652 z_bucket:0.06666666666666667 z_bucket_w:0.001 buckets:[0.06666666666666667 0.06666666666666667 0 0.06666666666666667 0.06666666666666667] n_buckets:[0.06666666666666667 0.06666666666666667 0 0.06666666666666667 0.06666666666666667]}}x1

clear

# Apply count and sum function to histogram.
load 10m
    histogram_count_sum_2 {{schema:0 count:24 sum:100 z_bucket:4 z_bucket_w:0.001 buckets:[2 3 0 1 4] n_buckets:[2 3 0 1 4]}}x1

eval instant at 10m histogram_count(histogram_count_sum_2)
    {} 24

eval instant at 10m histogram_sum(histogram_count_sum_2)
    {} 100

clear

# Apply stddev and stdvar function to histogram with {1, 2, 3, 4} (low res).
load 10m
   histogram_stddev_stdvar_1 {{schema:2 count:4 sum:10 buckets:[1 0 0 0 1 0 0 1 1]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_1)
    {} 1.0787993180043811

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_1)
    {} 1.163807968526718

clear

# Apply stddev and stdvar function to histogram with {1, 1, 1, 1} (high res).
load 10m
   histogram_stddev_stdvar_2 {{schema:8 count:10 sum:10 buckets:[1 2 3 4]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_2)
    {} 0.0048960313898237465

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_2)
    {} 2.3971123370139447e-05

clear

# Apply stddev and stdvar function to histogram with {-50, -8, 0, 3, 8, 9}.
load 10m
   histogram_stddev_stdvar_3 {{schema:3 count:7 sum:62 z_bucket:1 buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ] n_buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_3)
    {} 42.947236400258

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_3)
    {} 1844.4651144196398

clear

# Apply stddev and stdvar function to histogram with {-100000, -10000, -1000, -888, -888, -100, -50, -9, -8, -3}.
load 10m
   histogram_stddev_stdvar_4 {{schema:0 count:10 sum:-112946 z_bucket:0 n_buckets:[0 0 1 1 1 0 1 1 0 0 3 0 0 0 1 0 0 1]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_4)
    {} 27556.344499842

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_4)
    {} 759352122.1939945

clear

# Apply stddev and stdvar function to histogram with {-10x10}.
load 10m
   histogram_stddev_stdvar_5 {{schema:0 count:10 sum:-100 z_bucket:0 n_buckets:[0 0 0 0 10]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_5)
    {} 1.3137084989848

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_5)
    {} 1.725830020304794

clear

# Apply stddev and stdvar function to histogram with {-50, -8, 0, 3, 8, 9, NaN}.
load 10m
   histogram_stddev_stdvar_6 {{schema:3 count:7 sum:NaN z_bucket:1 buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ] n_buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_6)
    {} NaN

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_6)
    {} NaN

clear

# Apply stddev and stdvar function to histogram with {-50, -8, 0, 3, 8, 9, Inf}.
load 10m
   histogram_stddev_stdvar_7 {{schema:3 count:7 sum:Inf z_bucket:1 buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ] n_buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ]}}x1

eval instant at 10m histogram_stddev(histogram_stddev_stdvar_7)
    {} Inf

eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_7)
    {} Inf

clear

# Apply quantile function to histogram with all positive buckets with zero bucket.
load 10m
    histogram_quantile_1 {{schema:0 count:12 sum:100 z_bucket:2 z_bucket_w:0.001 buckets:[2 3 0 1 4]}}x1

eval_warn instant at 10m histogram_quantile(1.001, histogram_quantile_1)
    {} Inf

eval instant at 10m histogram_quantile(1, histogram_quantile_1)
    {} 16

eval instant at 10m histogram_quantile(0.99, histogram_quantile_1)
    {} 15.759999999999998

eval instant at 10m histogram_quantile(0.9, histogram_quantile_1)
    {} 13.600000000000001

eval instant at 10m histogram_quantile(0.6, histogram_quantile_1)
    {} 4.799999999999997

eval instant at 10m histogram_quantile(0.5, histogram_quantile_1)
    {} 1.6666666666666665

eval instant at 10m histogram_quantile(0.1, histogram_quantile_1)
    {} 0.0006000000000000001

eval instant at 10m histogram_quantile(0, histogram_quantile_1)
    {} 0

eval_warn instant at 10m histogram_quantile(-1, histogram_quantile_1)
    {} -Inf

clear

# Apply quantile function to histogram with all negative buckets with zero bucket.
load 10m
    histogram_quantile_2 {{schema:0 count:12 sum:100 z_bucket:2 z_bucket_w:0.001 n_buckets:[2 3 0 1 4]}}x1

eval_warn instant at 10m histogram_quantile(1.001, histogram_quantile_2)
    {} Inf

eval instant at 10m histogram_quantile(1, histogram_quantile_2)
    {} 0

eval instant at 10m histogram_quantile(0.99, histogram_quantile_2)
    {} -6.000000000000048e-05

eval instant at 10m histogram_quantile(0.9, histogram_quantile_2)
    {} -0.0005999999999999996

eval instant at 10m histogram_quantile(0.5, histogram_quantile_2)
    {} -1.6666666666666667

eval instant at 10m histogram_quantile(0.1, histogram_quantile_2)
    {} -13.6

eval instant at 10m histogram_quantile(0, histogram_quantile_2)
    {} -16

eval_warn instant at 10m histogram_quantile(-1, histogram_quantile_2)
    {} -Inf

clear

# Apply quantile function to histogram with both positive and negative buckets with zero bucket.
load 10m
    histogram_quantile_3 {{schema:0 count:24 sum:100 z_bucket:4 z_bucket_w:0.001 buckets:[2 3 0 1 4] n_buckets:[2 3 0 1 4]}}x1

eval_warn instant at 10m histogram_quantile(1.001, histogram_quantile_3)
    {} Inf

eval instant at 10m histogram_quantile(1, histogram_quantile_3)
    {} 16

eval instant at 10m histogram_quantile(0.99, histogram_quantile_3)
    {} 15.519999999999996

eval instant at 10m histogram_quantile(0.9, histogram_quantile_3)
    {} 11.200000000000003

eval instant at 10m histogram_quantile(0.7, histogram_quantile_3)
    {} 1.2666666666666657

eval instant at 10m histogram_quantile(0.55, histogram_quantile_3)
    {} 0.0006000000000000005

eval instant at 10m histogram_quantile(0.5, histogram_quantile_3)
    {} 0

eval instant at 10m histogram_quantile(0.45, histogram_quantile_3)
    {} -0.0005999999999999996

eval instant at 10m histogram_quantile(0.3, histogram_quantile_3)
    {} -1.266666666666667

eval instant at 10m histogram_quantile(0.1, histogram_quantile_3)
    {} -11.2

eval instant at 10m histogram_quantile(0.01, histogram_quantile_3)
    {} -15.52

eval instant at 10m histogram_quantile(0, histogram_quantile_3)
    {} -16

eval_warn instant at 10m histogram_quantile(-1, histogram_quantile_3)
    {} -Inf

clear

# Apply fraction function to empty histogram.
load 10m
    histogram_fraction_1 {{}}x1

eval instant at 10m histogram_fraction(3.1415, 42, histogram_fraction_1)
    {} NaN

clear

# Apply fraction function to histogram with positive and zero buckets.
load 10m
    histogram_fraction_2 {{schema:0 count:12 sum:100 z_bucket:2 z_bucket_w:0.001 buckets:[2 3 0 1 4]}}x1

eval instant at 10m histogram_fraction(0, +Inf, histogram_fraction_2)
    {} 1

eval instant at 10m histogram_fraction(-Inf, 0, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-0.001, 0, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(0, 0.001, histogram_fraction_2)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(0, 0.0005, histogram_fraction_2)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(0.001, inf, histogram_fraction_2)
    {} 0.8333333333333334

eval instant at 10m histogram_fraction(-inf, -0.001, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(1, 2, histogram_fraction_2)
    {} 0.25

eval instant at 10m histogram_fraction(1.5, 2, histogram_fraction_2)
    {} 0.125

eval instant at 10m histogram_fraction(1, 8, histogram_fraction_2)
    {} 0.3333333333333333

eval instant at 10m histogram_fraction(1, 6, histogram_fraction_2)
    {} 0.2916666666666667

eval instant at 10m histogram_fraction(1.5, 6, histogram_fraction_2)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(-2, -1, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-2, -1.5, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-8, -1, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-6, -1, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-6, -1.5, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(42, 3.1415, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(0, 0, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(0.000001, 0.000001, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(42, 42, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(-3.1, -3.1, histogram_fraction_2)
    {} 0

eval instant at 10m histogram_fraction(3.1415, NaN, histogram_fraction_2)
    {} NaN

eval instant at 10m histogram_fraction(NaN, 42, histogram_fraction_2)
    {} NaN

eval instant at 10m histogram_fraction(NaN, NaN, histogram_fraction_2)
    {} NaN

eval instant at 10m histogram_fraction(-Inf, +Inf, histogram_fraction_2)
    {} 1

# Apply fraction function to histogram with negative and zero buckets.
load 10m
    histogram_fraction_3 {{schema:0 count:12 sum:100 z_bucket:2 z_bucket_w:0.001 n_buckets:[2 3 0 1 4]}}x1

eval instant at 10m histogram_fraction(0, +Inf, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(-Inf, 0, histogram_fraction_3)
    {} 1

eval instant at 10m histogram_fraction(-0.001, 0, histogram_fraction_3)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(0, 0.001, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(-0.0005, 0, histogram_fraction_3)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(0.001, inf, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(-inf, -0.001, histogram_fraction_3)
    {} 0.8333333333333334

eval instant at 10m histogram_fraction(1, 2, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(1.5, 2, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(1, 8, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(1, 6, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(1.5, 6, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(-2, -1, histogram_fraction_3)
    {} 0.25

eval instant at 10m histogram_fraction(-2, -1.5, histogram_fraction_3)
    {} 0.125

eval instant at 10m histogram_fraction(-8, -1, histogram_fraction_3)
    {} 0.3333333333333333

eval instant at 10m histogram_fraction(-6, -1, histogram_fraction_3)
    {} 0.2916666666666667

eval instant at 10m histogram_fraction(-6, -1.5, histogram_fraction_3)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(42, 3.1415, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(0, 0, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(0.000001, 0.000001, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(42, 42, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(-3.1, -3.1, histogram_fraction_3)
    {} 0

eval instant at 10m histogram_fraction(3.1415, NaN, histogram_fraction_3)
    {} NaN

eval instant at 10m histogram_fraction(NaN, 42, histogram_fraction_3)
    {} NaN

eval instant at 10m histogram_fraction(NaN, NaN, histogram_fraction_3)
    {} NaN

eval instant at 10m histogram_fraction(-Inf, +Inf, histogram_fraction_3)
    {} 1

clear

# Apply fraction function to histogram with both positive, negative and zero buckets.
load 10m
    histogram_fraction_4 {{schema:0 count:24 sum:100 z_bucket:4 z_bucket_w:0.001 buckets:[2 3 0 1 4] n_buckets:[2 3 0 1 4]}}x1

eval instant at 10m histogram_fraction(0, +Inf, histogram_fraction_4)
    {} 0.5

eval instant at 10m histogram_fraction(-Inf, 0, histogram_fraction_4)
    {} 0.5

eval instant at 10m histogram_fraction(-0.001, 0, histogram_fraction_4)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(0, 0.001, histogram_fraction_4)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(-0.0005, 0.0005, histogram_fraction_4)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(0.001, inf, histogram_fraction_4)
    {} 0.4166666666666667

eval instant at 10m histogram_fraction(-inf, -0.001, histogram_fraction_4)
    {} 0.4166666666666667

eval instant at 10m histogram_fraction(1, 2, histogram_fraction_4)
    {} 0.125

eval instant at 10m histogram_fraction(1.5, 2, histogram_fraction_4)
    {} 0.0625

eval instant at 10m histogram_fraction(1, 8, histogram_fraction_4)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(1, 6, histogram_fraction_4)
    {} 0.14583333333333334

eval instant at 10m histogram_fraction(1.5, 6, histogram_fraction_4)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(-2, -1, histogram_fraction_4)
    {} 0.125

eval instant at 10m histogram_fraction(-2, -1.5, histogram_fraction_4)
    {} 0.0625

eval instant at 10m histogram_fraction(-8, -1, histogram_fraction_4)
    {} 0.16666666666666666

eval instant at 10m histogram_fraction(-6, -1, histogram_fraction_4)
    {} 0.14583333333333334

eval instant at 10m histogram_fraction(-6, -1.5, histogram_fraction_4)
    {} 0.08333333333333333

eval instant at 10m histogram_fraction(42, 3.1415, histogram_fraction_4)
    {} 0

eval instant at 10m histogram_fraction(0, 0, histogram_fraction_4)
    {} 0

eval instant at 10m histogram_fraction(0.000001, 0.000001, histogram_fraction_4)
    {} 0

eval instant at 10m histogram_fraction(42, 42, histogram_fraction_4)
    {} 0

eval instant at 10m histogram_fraction(-3.1, -3.1, histogram_fraction_4)
    {} 0

eval instant at 10m histogram_fraction(3.1415, NaN, histogram_fraction_4)
    {} NaN

eval instant at 10m histogram_fraction(NaN, 42, histogram_fraction_4)
    {} NaN

eval instant at 10m histogram_fraction(NaN, NaN, histogram_fraction_4)
    {} NaN

eval instant at 10m histogram_fraction(-Inf, +Inf, histogram_fraction_4)
    {} 1

eval instant at 10m histogram_sum(scalar(histogram_fraction(-Inf, +Inf, sum(histogram_fraction_4))) * histogram_fraction_4)
    {} 100

# Apply multiplication and division operator to histogram.
load 10m
    histogram_mul_div {{schema:0 count:30 sum:33 z_bucket:3 z_bucket_w:0.001 buckets:[3 3 3] n_buckets:[6 6 6]}}x1
    float_series_3 3+0x1
    float_series_0 0+0x1

eval instant at 10m histogram_mul_div*3
    {} {{schema:0 count:90 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[18 18 18]}}

eval instant at 10m histogram_mul_div*-1
    {} {{schema:0 count:-30 sum:-33 z_bucket:-3 z_bucket_w:0.001 buckets:[-3 -3 -3] n_buckets:[-6 -6 -6]}}

eval instant at 10m -histogram_mul_div
    {} {{schema:0 count:-30 sum:-33 z_bucket:-3 z_bucket_w:0.001 buckets:[-3 -3 -3] n_buckets:[-6 -6 -6]}}

eval instant at 10m histogram_mul_div*-3
    {} {{schema:0 count:-90 sum:-99 z_bucket:-9 z_bucket_w:0.001 buckets:[-9 -9 -9] n_buckets:[-18 -18 -18]}}

eval instant at 10m 3*histogram_mul_div
    {} {{schema:0 count:90 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[18 18 18]}}

eval instant at 10m histogram_mul_div*float_series_3
    {} {{schema:0 count:90 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[18 18 18]}}

eval instant at 10m float_series_3*histogram_mul_div
    {} {{schema:0 count:90 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[18 18 18]}}

eval instant at 10m histogram_mul_div/3
    {} {{schema:0 count:10 sum:11 z_bucket:1 z_bucket_w:0.001 buckets:[1 1 1] n_buckets:[2 2 2]}}

eval instant at 10m histogram_mul_div/-3
    {} {{schema:0 count:-10 sum:-11 z_bucket:-1 z_bucket_w:0.001 buckets:[-1 -1 -1] n_buckets:[-2 -2 -2]}}

eval instant at 10m histogram_mul_div/float_series_3
    {} {{schema:0 count:10 sum:11 z_bucket:1 z_bucket_w:0.001 buckets:[1 1 1] n_buckets:[2 2 2]}}

eval instant at 10m histogram_mul_div*0
    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}

eval instant at 10m 0*histogram_mul_div
    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}

eval instant at 10m histogram_mul_div*float_series_0
    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}

eval instant at 10m float_series_0*histogram_mul_div
    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}

# TODO: (NeerajGartia21) remove all the histogram buckets in case of division with zero. See: https://github.com/prometheus/prometheus/issues/13934
eval instant at 10m histogram_mul_div/0
    {} {{schema:0 count:Inf sum:Inf z_bucket:Inf z_bucket_w:0.001 buckets:[Inf Inf Inf] n_buckets:[Inf Inf Inf]}}

eval instant at 10m histogram_mul_div/float_series_0
    {} {{schema:0 count:Inf sum:Inf z_bucket:Inf z_bucket_w:0.001 buckets:[Inf Inf Inf] n_buckets:[Inf Inf Inf]}}

eval instant at 10m histogram_mul_div*0/0
    {} {{schema:0 count:NaN sum:NaN z_bucket:NaN z_bucket_w:0.001 buckets:[NaN NaN NaN] n_buckets:[NaN NaN NaN]}}

clear

# Counter reset only noticeable in a single bucket.
load 5m
     reset_in_bucket {{schema:0 count:4 sum:5 buckets:[1 2 1]}} {{schema:0 count:5 sum:6 buckets:[1 1 3]}} {{schema:0 count:6 sum:7 buckets:[1 2 3]}}

eval instant at 10m increase(reset_in_bucket[15m])
     {} {{count:9 sum:10.5 buckets:[1.5 3 4.5]}}

# The following two test the "fast path" where only sum and count is decoded.
eval instant at 10m histogram_count(increase(reset_in_bucket[15m]))
     {} 9

eval instant at 10m histogram_sum(increase(reset_in_bucket[15m]))
     {} 10.5

clear

# Test native histograms with custom buckets.
load 5m
    custom_buckets_histogram {{schema:-53 sum:5 count:4 custom_values:[5 10] buckets:[1 2 1]}}x10

eval instant at 5m histogram_fraction(5, 10, custom_buckets_histogram)
    {} 0.5

eval instant at 5m histogram_quantile(0.5, custom_buckets_histogram)
    {} 7.5

eval instant at 5m sum(custom_buckets_histogram)
    {} {{schema:-53 sum:5 count:4 custom_values:[5 10] buckets:[1 2 1]}}

clear

# Test 'this native histogram metric is not a gauge' warning for rate
load 30s
    some_metric {{schema:0 sum:1 count:1 buckets:[1] counter_reset_hint:gauge}} {{schema:0 sum:2 count:2 buckets:[2] counter_reset_hint:gauge}} {{schema:0 sum:3 count:3 buckets:[3] counter_reset_hint:gauge}}

# Test the case where we only have two points for rate
eval_warn instant at 30s rate(some_metric[1m])
    {} {{count:0.03333333333333333 sum:0.03333333333333333 buckets:[0.03333333333333333]}}

# Test the case where we have more than two points for rate
eval_warn instant at 1m rate(some_metric[1m])
    {} {{count:0.03333333333333333 sum:0.03333333333333333 buckets:[0.03333333333333333]}}

clear

# Test rate() over mixed exponential and custom buckets.
load 30s
    some_metric {{schema:0 sum:1 count:1 buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:0 sum:5 count:4 buckets:[1 2 1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}

# Start and end with exponential, with custom in the middle.
eval_warn instant at 1m rate(some_metric[1m])
    # Should produce no results.

# Start and end with custom, with exponential in the middle.
eval_warn instant at 1m30s rate(some_metric[1m])
    # Should produce no results.

# Start with custom, end with exponential.
eval_warn instant at 1m rate(some_metric[1m])
    # Should produce no results.

# Start with exponential, end with custom.
eval_warn instant at 30s rate(some_metric[1m])
    # Should produce no results.

clear

# Histogram with constant buckets.
load 1m
    const_histogram {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}}

# There is no change to the bucket count over time, thus rate is 0 in each bucket.
# However native histograms do not represent empty buckets, so here the zeros are implicit.
eval instant at 5m rate(const_histogram[5m])
    {} {{schema:0 sum:0 count:0}}

# Zero buckets mean no observations, thus the denominator in the average is 0
# leading to 0/0, which is NaN.
eval instant at 5m histogram_avg(rate(const_histogram[5m]))
    {} NaN

# Zero buckets mean no observations, so count is 0.
eval instant at 5m histogram_count(rate(const_histogram[5m]))
    {} 0.0

# Zero buckets mean no observations and empty histogram has a sum of 0 by definition.
eval instant at 5m histogram_sum(rate(const_histogram[5m]))
    {} 0.0

# Zero buckets mean no observations, thus the denominator in the fraction is 0,
# leading to 0/0, which is NaN.
eval instant at 5m histogram_fraction(0.0, 1.0, rate(const_histogram[5m]))
    {} NaN

# Workaround to calculate the observation count corresponding to NaN fraction.
eval instant at 5m histogram_count(rate(const_histogram[5m])) == 0.0 or histogram_fraction(0.0, 1.0, rate(const_histogram[5m])) * histogram_count(rate(const_histogram[5m]))
    {} 0.0

# Zero buckets mean no observations, so there is no value that observations fall below,
# which means that any quantile is a NaN.
eval instant at 5m histogram_quantile(1.0, rate(const_histogram[5m]))
    {} NaN

# Zero buckets mean no observations, so there is no standard deviation.
eval instant at 5m histogram_stddev(rate(const_histogram[5m]))
    {} NaN

# Zero buckets mean no observations, so there is no standard variance.
eval instant at 5m histogram_stdvar(rate(const_histogram[5m]))
    {} NaN

clear

# Test mixing exponential and custom buckets.
load 6m
  metric{series="exponential"}         {{sum:4 count:3 buckets:[1 2 1]}}  _                                                                 {{sum:4 count:3 buckets:[1 2 1]}}
  metric{series="other-exponential"}   {{sum:3 count:2 buckets:[1 1 1]}}  _                                                                 {{sum:3 count:2 buckets:[1 1 1]}}
  metric{series="custom"}              _                                  {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}     {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
  metric{series="other-custom"}        _                                  {{schema:-53 sum:15 count:2 custom_values:[5 10] buckets:[0 2]}}  {{schema:-53 sum:15 count:2 custom_values:[5 10] buckets:[0 2]}}

# T=0: only exponential
# T=6: only custom
# T=12: mixed, should be ignored and emit a warning
eval_warn range from 0 to 12m step 6m sum(metric)
  {} {{sum:7 count:5 buckets:[2 3 2]}} {{schema:-53 sum:16 count:3 custom_values:[5 10] buckets:[1 2]}} _

eval_warn range from 0 to 12m step 6m avg(metric)
  {} {{sum:3.5 count:2.5 buckets:[1 1.5 1]}} {{schema:-53 sum:8 count:1.5 custom_values:[5 10] buckets:[0.5 1]}} _

clear

# Test incompatible custom bucket schemas.
load 6m
  metric{series="1"} _                                                             {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
  metric{series="2"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}    _                                                             {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}
  metric{series="3"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}

# T=0: incompatible, should be ignored and emit a warning
# T=6: compatible
# T=12: incompatible followed by compatible, should be ignored and emit a warning
eval_warn range from 0 to 12m step 6m sum(metric)
  {} _ {{schema:-53 sum:2 count:2 custom_values:[5 10] buckets:[2]}} _

eval_warn range from 0 to 12m step 6m avg(metric)
  {} _ {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} _

clear

load 1m
  metric{group="just-floats", series="1"} 2
  metric{group="just-floats", series="2"} 3
  metric{group="just-exponential-histograms", series="1"} {{sum:3 count:4 buckets:[1 2 1]}}
  metric{group="just-exponential-histograms", series="2"} {{sum:2 count:3 buckets:[1 1 1]}}
  metric{group="just-custom-histograms", series="1"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}
  metric{group="just-custom-histograms", series="2"} {{schema:-53 sum:3 count:4 custom_values:[2] buckets:[7]}}
  metric{group="floats-and-histograms", series="1"} 2
  metric{group="floats-and-histograms", series="2"} {{sum:2 count:3 buckets:[1 1 1]}}
  metric{group="exponential-and-custom-histograms", series="1"} {{sum:2 count:3 buckets:[1 1 1]}}
  metric{group="exponential-and-custom-histograms", series="2"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
  metric{group="incompatible-custom-histograms", series="1"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
  metric{group="incompatible-custom-histograms", series="2"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}

eval_warn instant at 0 sum by (group) (metric)
  {group="just-floats"} 5
  {group="just-exponential-histograms"} {{sum:5 count:7 buckets:[2 3 2]}}
  {group="just-custom-histograms"} {{schema:-53 sum:4 count:5 custom_values:[2] buckets:[8]}}

clear

# Test native histograms with sum, count, avg.
load 10m
    histogram_sum{idx="0"} {{schema:0 count:25 sum:1234.5 z_bucket:4 z_bucket_w:0.001 buckets:[1 2 0 1 1] n_buckets:[2 4 0 0 1 9]}}x1
    histogram_sum{idx="1"} {{schema:0 count:41 sum:2345.6 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}}x1
    histogram_sum{idx="2"} {{schema:0 count:41 sum:1111.1 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}}x1
    histogram_sum{idx="3"} {{schema:1 count:0}}x1
    histogram_sum_float{idx="0"} 42.0x1

eval instant at 10m sum(histogram_sum)
    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}

eval_warn instant at 10m sum({idx="0"})

eval instant at 10m sum(histogram_sum{idx="0"} + ignoring(idx) histogram_sum{idx="1"} + ignoring(idx) histogram_sum{idx="2"} + ignoring(idx) histogram_sum{idx="3"})
    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}

eval instant at 10m count(histogram_sum)
    {} 4

eval instant at 10m avg(histogram_sum)
    {} {{schema:0 count:26.75 sum:1172.8 z_bucket:3.5 z_bucket_w:0.001 buckets:[0.75 2 0.5 1.25 0.75 0.5 0.5] n_buckets:[0.5 1.5 2 1 3.75 2.25 0 0 0 2.5 2.5 1]}}

clear

# Test native histograms with sum_over_time, avg_over_time.
load 1m
    histogram_sum_over_time {{schema:0 count:25 sum:1234.5 z_bucket:4 z_bucket_w:0.001 buckets:[1 2 0 1 1] n_buckets:[2 4 0 0 1 9]}} {{schema:0 count:41 sum:2345.6 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}} {{schema:0 count:41 sum:1111.1 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}} {{schema:1 count:0}}

eval instant at 3m sum_over_time(histogram_sum_over_time[4m:1m])
    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}

eval instant at 3m avg_over_time(histogram_sum_over_time[4m:1m])
    {} {{schema:0 count:26.75 sum:1172.8 z_bucket:3.5 z_bucket_w:0.001 buckets:[0.75 2 0.5 1.25 0.75 0.5 0.5] n_buckets:[0.5 1.5 2 1 3.75 2.25 0 0 0 2.5 2.5 1]}}