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Questions tagged [histogram]

In statistics, a histogram is a graphical representation, showing a visual impression of the distribution of data.

In statistics, a histogram is a graphical representation, showing a visual impression of the distribution of data. It is an estimate of the probability distribution of a continuous variable and was first introduced by Karl Pearson. A histogram consists of tabular frequencies, shown as adjacent rectangles, erected over discrete intervals (bins), with an area equal to the of the observations in the interval. The height of a rectangle is also equal to the frequency density of the interval, i.e., the frequency divided by the width of the interval. The total area of the histogram is equal to the number of data. A histogram may also be normalized displaying relative frequencies. It then shows the proportion of cases that fall into each of several categories, with the total area equaling 1. The categories are usually specified as consecutive, non-overlapping intervals of a variable. The categories (intervals) must be adjacent, and often are chosen to be of the same size.

Histograms are used to plot density of data, and often for density estimation: estimating the probability density function of the underlying variable. The total area of a histogram used for probability density is always normalized to 1. If the length of the intervals on the x-axis are all 1, then a histogram is identical to a relative frequency plot.

In scientific software for statistical computing and graphics, The function hist generates a histogram. It can also optionally scale it so that its total area is 1. This puts it in the right scale if one want to overlay a probability density curve.

More about it here : histogram wiki

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How to add an histogram to estimator's train() and eval() cycles

I'm using a tf.contrib.estimator.DNNEstimator and I'd like to add my custom histogram to it which would be calculated from the labels and predictions. I've seen I can very easily add a scalar metric with tf.contrib.estimator.add_metrics() but I…
galderic
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What is the automatic binning algorithm used in MATLAB's histogram function?

An automatic binning algorithm was used in the default bin selection of the histogram function in MATLAB. On the documentation however, there is no mention of the reference material/publication used for implementing this. What is this algorithm?
User2201
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Histogram should not show data just the histogram itself

I am trying to plot histogram using angular 4. I would be having an array of data consisting 1000 values each. if there are two arrays, I should be able to show histgrams. The requirement is that only the histogram needs to be plotted not the data.…
Tom
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Can't change the colors on a ggplot2 histogram

I'm working with a dataset of 5k finish times that looks a little bit like this: "15:34" "14:23" "17:34" and so on, there's a lot, but they're all formatted like that. I'm able to convert all of them to POSIXct, and store them in a data frame to…
Matthew Rogers
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Creating a secondary y-axis in histogram

I have found multiple ways to create a secondary y-axis in plot but I couldn't find a way to create a secondary y-axis in histogram. Here is a sample code: a <- sample(90:110, 50, replace=TRUE) b <- runif(50, min=0, max=1) hist(a) lines(b) b is too…
Y. Z.
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Assign a plot to a variable

How can I save a matplotlib.pyplot as variable/image/numpy.array of a specific size ((1280, 720, 3) or (1280, 720, 1)) import matplotlib.pyplot as plt import random data = [random.randint(1, 100) for _ in range(100)] fig =…
Trenera
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What does the parameter "bins" signify in dataframe.hist()?

I'm learning ML from a book in which the writer wrote: housing.hist(bins=50, figsize=(20,15)) plt.show() - to draw histogram of the data. In there, I didn't understand the significance and need of bin attribute and how to decide a value for it. I…
Aniruddh Sharma
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How to get the same bin widths for variable bin ranges in a histogram using Python?

I am trying to create a histogram with a custom bin range. However, as you can see in the histogram below, the bin widths are not a constant size. Ideally, I want something like this. The spacing between bins doesn't really matter, I just want…
jlcv
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Changing the relative height of the bins of a histogram interactively

In subjective probability assessments one needs to elicit the distribution of subjects believes. It can be achieved by letting the subject manipulate the relative height of each frequency bin of a histogram. I.e. the distribution of probability, the…
Roland Kofler
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Print histogram in python 3

I have a word length_of_word | repetitions dictionary and I want to make a histogram of that like the one in link below using only python built in functions no numpy or anything like it. http://dev.collabshot.com/show/723400/ Please help me out at…
maumercado
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Relative frequency histogram plot of a numeric variable in massive dataset

I have a numerical variable "myvariable" of 14e^06 elements which I want to plot a histogram to show the relative frequency of each bin. Considering the following sample data: set.seed(1234) wdata = data.frame( sex = factor(rep(c("F", "M"),…
Seymour
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Change matplotlib.bar Order in python 2.7

In this example: import matplotlib.pyplot as plt colors = ['white', 'orange', 'green', 'purple'] rates = ['5','5','4','3'] plt.bar(colors, rates) the bars in the plot are ordered by the alphabetic order. How do I make them to show in the same…
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Histogram Bars not Centred over xticks in pyplot.hist

I guess I just didn't use the right keywords, because this probably has been asked before, but I didn't find a solution. Anyway, I have a problem where the the bars of a histogram do not line up with the xticks. I want the bars to be centred over…
lo tolmencre
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Compare two vectors in a histogram

I have two vectors, for example price1 = [28688, 28241, 30091] price2 =[27285, 29924, 35291] that I need to put in a histogram in order to visualize the differences and to compare them element by element. What I have tried was ind =…
Francesco Di Lauro
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R: Group intersections in circos plots showing extra band with variable values

I have a data frame that looks like the following: set.seed(1) mydf <- data.frame() for (g in LETTERS[1:4]){ m <- data.frame(Group=g, Gene=paste(sample(letters[1:4],25,replace=TRUE), sample(1:25,25,replace=FALSE), sep=''), …
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