How and where can i set index for class?

milad66 · June 22, 2020, 2:21pm

Hi
how and where can i set index for class?
Thank You

ptrblck · June 23, 2020, 3:16am

You can set the class index manually, if you are creating the dataset.
If you are using a dataset from torchvision, such as MNIST, the classes would be already predefined.
For ImageFolder, the specified folders will be sorted and the class indices will be created according to the sorted folders starting at 0.

milad66 · June 23, 2020, 1:20pm

Thanks

Praveen_K · August 12, 2020, 11:37am

What sorting order is followed? if there is cat and dog folder , which one is index:0

ptrblck · August 12, 2020, 11:29pm

The order is determined by the sort() method used in this line of code, which might be OS-dependent. In your example, cat would most likely be class0 and dog class1 and you can check it via the dataset.class_to_index attribute.

However, there were differences on Windows and Linux in the sorting of names starting with numbers.
If I remember correctly, you would have to prepend zeros to the name to get the same sorting: