convolution1dLayer(5,100,'Padding',2,'Stride', 1)

This is a 1D convolutional layer in MATLAB with a filter size of 5 and 100 output channels. The 'Padding' parameter specifies that zero-padding should be added to the input data so that the output size is the same as the input size. The 'Stride' parameter specifies that the filter should move one step at a time along the input.

In other words, this layer applies a convolution operation on a 1D input signal using a filter of size 5, which will result in 100 output channels. The output size will be the same as the input size due to the padding, and the filter will move one step at a time. This layer is commonly used in deep learning models for tasks such as speech recognition, natural language processing, and time series analysis.