Modifing the weights of neural network by setting some weughts to zero

Is there way to access the weights of deep neural networks and set some weights to zero of pretrained model then compute the accuracy of the model. I am working in a project and I need to do the following steps:

1. train the model or download pretrained model
2. Set some weights to zeros
3. Do some computation (this is will be my work)
4. Test the model again (without trian it again)

I tried those steps on the model pretrind myself using AutoencoderDigitsExample and accessed to the weights for example

    autoenc1.EncoderWeights

but I could not modified the weights of the model when I did so

    autoenc1.EncoderWeights(1)=0

I recieved this error

     You cannot set the read-only property 'EncoderWeights' of Autoencoder.

So please I am looking for a way to accessing the weights of any neural network pretrrained model trained by Matlab.

[cedric MAGUETA RUIVO]

you can transform the autoencoder object into a neural network object with the network fonction and then use the IW and LW properties

net=network(autoenc);
net.IW{1}(1,1)=0; % set the first weigth of the first layer to zero

but with this methode ou can not more use the encode or decode function