google/benchmark

Introduce scientific notation for counters in console

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#818 opened on May 13, 2019

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 (4 comments) (2 reactions) (0 assignees)C++ (7,968 stars) (1,539 forks)batch import
enhancementgood first issuehelp wanted

Description

Sometimes it becomes difficult to grasp immediately the differences between benchmarked functions that have a wide variance in a given counter. The aforementioned readability problem is due to the usage of the SI standard by default. This one below is an example where I am dealing with different functions to approximate sine, look at the absolute error calculated for each one: Screenshot_20190513_185727 It's not instantly obvious how much more precise the first function is, but it would be using scientific notation: Screenshot_20190513_202852

The usage might be as easy as:

state.counters["Foo"] = Counter(fooVal, benchmark::Counter::kScientificNotation);

Contributor guide

Tech stack
cpp
Domain
cliperformance
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
C++ programmingFamiliarity with Google Benchmark libraryBasic understanding of counters
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70
Research direction
The issue requests adding a kScientificNotation flag for counters to display values in scientific notation. Start by examining the Counter class definition in benchmark/benchmark.h to see existing flags. Then look at console output formatting in src/console reporter.cc to understand how counter values are currently printed. Review the 4 comments on the issue for any additional insights or constraints. The implementation likely involves adding a new flag constant and modifying the formatting logic based on that flag.