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

void rangeByIndex(size_t a_index) const

void rangeByIndex(size_t a_index, TItem a_min, size_t a_size) const

void rangeByIndex(size_t a_index, TItem a_min, TItem a_max) const

[STATIC] std::pair<TItem, TItem> rangeByIndex(size_t a_index, 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 a specific bin index.

The rangeByIndex method provides the mathematical boundaries for a specific bin index within the histogram.

This is useful when you are iterating through the histogram bins (e.g., for drawing a bar chart or generating a table) and need to know the actual value range that each bin represents.

Arguments

size_t a_index

- The zero-based index of the bin.

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 index.

Thrown exceptions

std::out_of_range - Thrown if the provided index is greater than or equal to the current number of bins.

Example: Iterating Through Bins

Using bin indices to determine the value ranges for all bins in the histogram.

#define FCF_TEST_IMPLEMENTATION #include <fcfTest/test.hpp> #include <iostream> FCF_TEST_DEFINE("HistogramDemo", "Basic", "IndexRangeCheck") { // Create a histogram with 5 bins in range [0, 50] fcf::NTest::HistogramBasic<int> hist(5, 0, 50); // 1. Get range for the 3rd bin (index 2) std::pair<int, int> range = hist.rangeByIndex(2); fcf::NTest::log() << "Bin 2 range: [" << range.first << " : " << range.second << "]" << std::endl; // 2. Verify the range for index 2 in a 5-bin [0, 50] setup (should be [20, 29]) FCF_TEST(range.first == 20 && range.second == 29); } 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" -> "IndexRangeCheck" ... > Bin 2 range: [20 : 29] [SUCCESS] Test completed successfully (0.000`010`382 sec) [SUCCESS] All tests were completed. Tests: 1 passed, 0 failed, 0 skipped, 1 total Duration: 0.000`010`382 sec

The rangeByIndex method is essential for generating visual representations like tables or charts.