4.35 Tuesday, April 18, 2017

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Top new questions this week: 
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[Crack CAPTCHA using deep learning] https://mathematica.stackexchange.com/questions/143691/crack-captcha-using-deep-learning

Deep convolutional neural networks are very good at computer vision related tasks. Optical Character Recognition (OCR) is one important branch of computer vision. In fact, the convolution neural ...

- asked by xslittlegrass (50 votes), answered by xslittlegrass (52 votes)

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[Changes to Series[...] in version 11.1] https://mathematica.stackexchange.com/questions/143414/changes-to-series-in-version-11-1

I have updated to Mathematica 11.1 and I am shocked to see that the Series-function now works differently:

If I enter

Series[x^2+x^3, {x,0,0}] 
 
 
it will return 
 
x^2+O[x]^3

which is just weird. In ...

- asked by Matthias Koenig (16 votes), answered by QuantumDot (3 votes)

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[WLNet format incompatible between version 11.0 and 11.1] https://mathematica.stackexchange.com/questions/143699/wlnet-format-incompatible-between-version-11-0-and-11-1

It seems that there are some behavior changes of neural network layers from version 11.0 to 11.1 that leads to the incompatibility of WLNet format.

Consider this example:

Network exported in 11.0

...

- asked by xslittlegrass (13 votes), answered by Taliesin Beynon (7 votes)

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[DSolve solution depends on ordering of equation] https://mathematica.stackexchange.com/questions/143726/dsolve-solution-depends-on-ordering-of-equation

Bug introduced in 8.0 or earlier and persisting through 11.1.0 or later

I am trying to obtain the general solution, \(G(x_1,x_2,x_3,x_4)\) to the very easy system of PDEs:

- asked by Jeremy Upsal (12 votes), answered by Nasser (8 votes)

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[Why the Callout option makes plotting performance poor] https://mathematica.stackexchange.com/questions/143711/why-the-callout-option-makes-plotting-performance-poor

Bug introduced in 11.0 and fixed in 11.1

The Callout option is a new option for plotting, but the performance is very poor, see bellow testing case.

num = 1000; 
list = N@Sin@Range[num]; 
list2 =  ...

- asked by Jerry (11 votes)

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[Neural machine translation model using deep learning] https://mathematica.stackexchange.com/questions/143609/neural-machine-translation-model-using-deep-learning

In Mathematica version 11.1, SequenceAttentionLayer is introduced to model attentions in the recurrent neural network. It has been shown that attention mechanism can greatly improve the quality of a ...

- asked by xslittlegrass (11 votes), answered by Sebastian (8 votes)

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[Backslide in NSolve in V11.1?] https://mathematica.stackexchange.com/questions/143824/backslide-in-nsolve-in-v11-1

In V11.1,

NSolve[BesselJ[0, x] == 0 && 0 < x < 20, x]

returns no solutions:

But in V11.0 (and earlier), it returns all solutions:

Is there anyway to get NSolve to solve this ...

- asked by Michael E2 (10 votes), answered by Nasser (8 votes)

================================== Greatest hits from previous weeks: ==================================

[How to perform a multi-peak fitting?] https://mathematica.stackexchange.com/questions/26336/how-to-perform-a-multi-peak-fitting

I am wondering how to implement the multi-peak detecting and fitting in Mathematica. Following is an example of fitting the data using three peaks (such that the data   peak1 + peak2 + peak3).

The ...

- asked by Everett You (43 votes), answered by Silvia (45 votes)

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[How to make an inkblot?] https://mathematica.stackexchange.com/questions/3345/how-to-make-an-inkblot

How to effectively create a polygon that looks like a realistic inkblot? So far, I could come up with this (borrowing from Ed Pegg Jr.’s Rorschach demonstration):

RandomBlot[num_, opts___] :=  ...

- asked by István Zachar (84 votes), answered by Sjoerd C. de Vries (47 votes)

================================== Can you answer these? ==================================

[How to create an APIFunction that takes a list with constraints on the list elements?] https://mathematica.stackexchange.com/questions/143709/how-to-create-an-apifunction-that-takes-a-list-with-constraints-on-the-list-elem

This APIFunction takes a list as an argument:

func = APIFunction[{"x" -> DelimitedSequence["Integer", ","]}, #x^3 &] 
 
func["x" -> Range[4]]

What I’d like to be able to do is place a ...

- asked by Mike Honeychurch (4 votes)

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[How to setup FrameTicks for TradingChart] https://mathematica.stackexchange.com/questions/143705/how-to-setup-frameticks-for-tradingchart

I’m trying to setup FrameTicks for TradingChart, but it dosn’t work.

(*take data*) 
data = FinancialData["NASDAQ:AAPL", "OHLCV", {{2017, 1, 1}, {2017, 4, 16}}]; 
 
(*def. of ticks*) 
maxh =  ...

- asked by Jerry (3 votes)

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[What are the software requirements to train neural networks on GPU?] https://mathematica.stackexchange.com/questions/143795/what-are-the-software-requirements-to-train-neural-networks-on-gpu

It seems that GPU training in Mathematica has some additional requirements on the software. For example, when I run this example on a Linux system, I get the following errors

trainingData = 
   ... 

- asked by xslittlegrass (8 votes)