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 Python Data Type Q&A » numpy » histogram

### 1. Numpy histogram of large arrays    stackoverflow.com

I have a bunch of csv datasets, about 10Gb in size each. I'd like to generate histograms from their columns. But it seems like the only way to do this in ...

### 2. python: using numpy.histogram    stackoverflow.com

i am using this: http://docs.scipy.org/doc/numpy/reference/generated/numpy.histogram.html i have an list `a` that i want to use like this:

``````numpy.histogram(a,bins=[0.1,0.2,0.3,0.4...6], range=[0:6])
``````
1. how do i include a set of bins 0.1 through 6 in 0.1 intervals?
2. how ...

### 3. How to create the histogram of an array with masked values, in Numpy?    stackoverflow.com

In Numpy 1.4.1, what is the simplest or most efficient way of calculating the histogram of a masked array? `numpy.histogram` and `pyplot.hist` do count the masked elements, by default! The only ...

### 4. Calculating Histogram from one-dimensional float arrays in OpenCV    stackoverflow.com

I want to create histogram and calculate it using `opencv` method `cv.CalcHist`. But my data is one-dimensional arrays instead of `IplImage` objects. Why does the following code produce zero histogram?:

``hist = ...``

### 5. numpy histogram with 3x3D arrays as indices    stackoverflow.com

I've got 3x3D arrays which are the red, green and blue channels of a 3D rgb image. What is an elegant way in numpy to to create a histogram volume of ...