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Questions tagged [measurement]

499 questions
398
votes
26 answers

Easily measure elapsed time

I am trying to use time() to measure various points of my program. What I don't understand is why the values in the before and after are the same? I understand this is not the best way to profile my program, I just want to see how long something…
hap497
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8 answers

How do I measure separate CPU core usage for a process?

Is there any way to measure a specific process CPU usage by cores? I know top is good for measuring the whole system's CPU usage by cores and taskset can provide information about which CPU core is allowed for the process to run on. But how do I…
elang
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10 answers

How can I measure the speed of code written in PHP?

How can I say which class of many (which all do the same job) execute faster? is there a software to measure that?
M. A. Kishawy
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121
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11 answers

Font size relative to the user's screen resolution?

I have a fluid website and the menu is 20% of its width. I want the font size of the menu to be measured properly so it always fits the width of the box and never wrap to the next line. I was thinking of using "em" as a unit but it is relative to…
barakuda28
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4 answers

simplest tool to measure C program cache hit/miss and cpu time in linux?

I'm writing a small program in C, and I want to measure it's performance. I want to see how much time do it run in the processor and how many cache hit+misses has it made. Information about context switches and memory usage would be nice to have…
jperelli
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5 answers

Units of a Fourier Transform (FFT) when doing Spectral Analysis of a Signal

My question has to do with the physical meaning of the results of doing a spectral analysis of a signal, or of throwing the signal into an FFT and interpreting what comes out using a suitable numerical package, Specifically: take a signal, say a…
Assad Ebrahim
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10 answers

Stopwatch class for Java

Which Java class should you use for time performance measurements? (One could use any date/time class, but the reason I'm asking is in .Net there's a designated Stopwatch class for this purpose)
ripper234
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4 answers

Memory usage of Docker containers

I am using Docker to run some containerized apps. I am interested in measuring how much resources they consume (as far as regarding CPU and Memory usage). Is there any way to measure the resources consumed by Docker containers like RAM & CPU…
Paris
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55
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6 answers

Difference between android dimension: pt and dp

The documentation says that 160 dp (density-independent) equals 1 inch. And 72 pt is also 1 inch. So I don't see why android define a dp measurement while it seems to work the same as points. Can anybody explain that? Why should I use dp if I can…
Herbert
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55
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2 answers

rem px in Javascript

I use this code in JS: bigPhoto.setAttribute("width", "200rem"); The result is in pixel in html source, But: When I change it to 20rem the photo become really small. I couldn't solve the problem which is mentioned in the photos.
Malus Jan
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2 answers

Why is Graphics.MeasureString() returning a higher than expected number?

I'm generating a receipt and am using the Graphics object to call the DrawString method to print out the required text. graphics.DrawString(string, font, brush, widthOfPage / 2F, yPoint, stringformat); This works fine for what I needed it to do. I…
Brandon
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7 answers

If I call getMeasuredWidth() or getWidth() for layout in onResume they return 0

If I call getMeasuredWidth() or getWidth() for layout in onResume they returns 0. I think that view it's not drawn yet in this moment. Also I think that I need to put getMeasuredWidth() or getWidth() in callback method called after layout is drawn…
mobiledev Alex
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2 answers

What is a bad, decent, good, and excellent F1-measure range?

I understand F1-measure is a harmonic mean of precision and recall. But what values define how good/bad a F1-measure is? I can't seem to find any references (google or academic) answering my question.
KubiK888
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4 answers

How can I measure pixels in Chrome without an extension?

Due to security limitations at work, I am not allowed to install Chrome extensions. Chrome has a ruler built in to the developer tools, but I can't figure out how to define start and end points like a ruler would permit. Are there any tools or…
adamdport
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14 answers

How do you measure page load speed?

I am trying to quantify "site slowness". In the olden days you just made sure that your HTML was lightweight, images optimized and servers not overloaded. In high end sites built on top of modern content management systems there are a lot more…
deadprogrammer
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