rangeByValue() method from fcf::NTest::HistogramBasic class

void rangeByValue(TItem a_value) const

void rangeByValue(TItem a_value, TItem a_min, size_t a_size) const

void rangeByValue(TItem a_value, TItem a_min, TItem a_max) const

[STATIC] std::pair<TItem, TItem> rangeByValue(TItem a_value, TItem a_min, TItem a_max, size_t a_size)

Class: fcf::NTest::HistogramBasic

Package: fcfTest

File: test.hpp

Available from version: 1.2.5

Calculates the lower and upper boundaries of the bin containing the specified value.

The rangeByValue method allows you to determine exactly which interval (bin) a specific value belongs to within the current histogram structure.

This is essential when you need to map a raw data point back to its corresponding histogram bin for detailed analysis or visualization.

Arguments

TItem a_value

- The value to locate within the range.

Result

std::pair<TItem, TItem>

- A pair where the first element is the lower bound and the second element is the upper bound of the bin.

Thrown exceptions

std::out_of_range - Thrown if the provided value is outside the specified [min, max] range.

Example: Finding Bin Boundaries

Calculating the range of a bin for a given value using the histogram's current state.

#define FCF_TEST_IMPLEMENTATION #include <fcfTest/test.hpp> #include <iostream> FCF_TEST_DEFINE("HistogramDemo", "Basic", "RangeCheck") { // Create a histogram with range [0, 100] and 10 bins fcf::NTest::HistogramBasic<double> hist(10, 0.0, 100.0); // 1. Find range for value 25.0 using current histogram state std::pair<double, double> range = hist.rangeByValue(25.0); fcf::NTest::log() << "Value 25.0 is in bin: [" << range.first << " : " << range.second << "]" << std::endl; // 2. Verify the math (for 10 bins in 0-100, 25.0 should be in [20.0, 29.0] or similar depending on implementation) FCF_TEST(range.first <= 25.0 && range.second >= 25.0); } int main(int a_argc, char* a_argv[]) { bool error = false; fcf::NTest::cmdRun(a_argc, a_argv, fcf::NTest::CRM_RUN, &error); return error ? 1 : 0; }

Output:

Performing the test: "HistogramDemo" -> "Basic" -> "RangeCheck" ... > Value 25.0 is in bin: [20 : 29] [SUCCESS] Test completed successfully (0.000`023`531 sec) [SUCCESS] All tests were completed. Tests: 1 passed, 0 failed, 0 skipped, 1 total Duration: 0.000`023`531 sec

The rangeByValue method is essential for mapping raw data back to its statistical bin.