millions of thanks for all the info. m. On Mon, Apr 15, 2013 at 1:21 AM, Paul Higham wrote:

Wouldn't it do just to have

nActivationSum = map nActivation

or am I missing your intent here?

Note that on the left-hand side of the last equation inputs would have to have type (Float, Float) and weights would have to have type [(Float,Float)], but on the right-hand side both inputs and weights have to be Float. The result of nActivation (inputs, weights) is Float, but the result of nActivationSum (inputs:weights) should be [(Float,Float)], hence the error message.

:: paul

On 2013-04-14, at 16:04 , Miro Karpis wrote:

Please can you help me with this? What I want is to have on input a list of tuple (size 2) and on output list of floats. So now I'm returning only float instead of a list. But unfortunately I can't figure out how to implement the list......

sigmoid :: Float -> Float sigmoid x = 1.0 / (1 + exp (-x))

nActivation :: (Float,Float) -> Float nActivation (x,y) = sigmoid(x*y)

nActivationSum :: [(Float, Float)] -> [Float] nActivationSum [] = [] nActivationSum (inputs:weights) = *nActivation* (inputs, weights)

Couldn't match expected type `[Float]' with actual type `Float' In the return type of a call of `nActivation' In the expression: nActivation (inputs, weights) In an equation for `nActivationSum': nActivationSum (inputs : weights) = nActivation (inputs, weights)

thanks, m. _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners