mat-file

ndim in numpy array loaded with scipy.io.loadmat?

旧巷老猫 提交于 2019-12-22 17:56:14
问题 Using SciPy and MATLAB, I'm having trouble reconstructing an array to match what is given from a MATLAB cell array loaded using scipy.io.loadmat(). For example, say I create a cell containing a pair of double arrays in MATLAB and then load it using scipy.io (I'm using SPM to do imaging analyses in conjunction with pynifti and the like) MATLAB >> onsets{1} = [0 30 60 90] >> onsets{2} = [15 45 75 105] Python >>> import scipy.io as scio >>> mat = scio.loadmat('onsets.mat') >>> mat['onsets'][0]

How to preserve matlab struct when accessing in python?

徘徊边缘 提交于 2019-12-20 19:37:22
问题 I have a mat-file that I accessed using from scipy import io mat = io.loadmat('example.mat') From matlab, example.mat contains the following struct >> load example.mat >> data1 data1 = LAT: [53x1 double] LON: [53x1 double] TIME: [53x1 double] units: {3x1 cell} >> data2 data2 = LAT: [100x1 double] LON: [100x1 double] TIME: [100x1 double] units: {3x1 cell} In matlab, I can access data as easy as data2.LON, etc.. It's not as trivial in python. It give me several option though like mat.clear mat

How to append in .mat file row or columnwise cellmatrix

一笑奈何 提交于 2019-12-19 10:19:49
问题 I am running a simulation where i generate huge 2d sparse matrices and hence i use FIND function to only store nonzero values with their indices. Now for each iteration of for loop i generate such matrix and because they are all of different length I use cell-array to store these configurations. But for large simulations even squeezed-off format of cell-array crosses its limits of memory and hence i want to write these cell-array while running the code i.e. for each iteration append a new

How can I load part of a .mat file that is too big in memory for my machine?

混江龙づ霸主 提交于 2019-12-18 04:11:34
问题 I have a big .mat file that I want to process, but it is too big to fit in a single load. I thought to load it in parts, each time to access just the important parameters. So I have practically two questions: How can I access the variables names of the mat file without loading it? How can I load only one of them to the workspace? Thanks! 回答1: you can see the list of variables using: vars = whos('-file','name.mat'); and then just load the variable you want, say the first one on the list, by:

Armadillo reading MAT file error

我只是一个虾纸丫 提交于 2019-12-13 18:11:49
问题 I'm currently cross-compiling on the BeagleBone Black in a Visual Studio environment using Armadillo to translate MATLAB code into C++. This is a signal processing project, so I need a way to read and write binary data files, specifically .mat files. Thankfully, the armadillo documentation says that you can load .mat files directly into a matrix using .load() I attempted that at first, but it seems like it's not reading the file correctly, nor is it reading all the entries. My reference file

Creating a .mat file of v7.3 in python

*爱你&永不变心* 提交于 2019-12-13 02:21:20
问题 I need to perform multiplication involving 60000X70000 matrix either in python or matlab. I have a 16GB RAM and am able to load each row of the matrix easily (which is what I require). I am able to create the matrix as a whole in python but not in matlab. Is there anyway I can save the array as .mat file of v7.3 using h5py or scipy so that I can load each row separately? 回答1: For MATLAB v7.3 you can use hdf5storage which requires h5py , download the file here, extract, then type: python setup

Load part of matfile error: 'VARName' does not exist

夙愿已清 提交于 2019-12-12 04:37:56
问题 i'm trying to load part of array in a matfile like is showed in http://www.mathworks.com/help/matlab/ref/matfile.html however, when i use loadedData = matObj.varName(indices) i keep getting: 'varName' does not exist someone knows what's rong? 回答1: In place of VarName you should use the name of the actual variable you want to retrieve. Suppose you have saved a variable A into myMat : A = rand(10); save('myMat','A','-v7.3') matObj = matfile('myMat'); data = matObj.A(1:2,2); 来源: https:/

Why does saving/loading data in python take a lot more space/time than matlab?

旧时模样 提交于 2019-12-12 04:37:28
问题 I have some variables, which include dictionaries, list of list, and numpy arrays. I save all of them with the following code, where obj=[var1,var2,...,varn]. The variables size is small enough to be loaded in memory. My problem is when I save the corresponding variables in matlab the output file takes a lot less space on the disk than doing it in python. Similarly, loading the variables from the disk takes a lot more time to be loaded in memory in python than matlab. with open(filename, 'wb'

Memory issue with Matlab: update variable in .mat

岁酱吖の 提交于 2019-12-11 14:24:16
问题 I am working with a very computational expansive code in Matlab. It requires the usage of optimisation techniques and long computations using very big matrixes. I am having the following issue: even if the code run correctly, at the end of the iterations required by the code, Matlab is not storing the biggest cell arrays that I have. I guess that it is due to some memory inefficiency in my code or with my computer (which is probably not sufficiently powerful). However, I followed all the

how to import a matlab table in R

你说的曾经没有我的故事 提交于 2019-12-11 10:17:39
问题 I have a matlab .mat file with table data type which I want to import in R. I am using 'readMat' for this and R is reading it as a List. After that is there a way to convert the list into either a dataframe or table format in R? When I use as.dataframe I get the following error : Error in (function (..., row.names = NULL, check.rows = FALSE, check.names = TRUE, : arguments imply differing number of rows: 5, 6, 1 A possible workaround I thought of is to export the table as a .csv from matlab