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Mastering Development

Why some LPeg substitutions don’t show up when there are many levels of captures in an LPeg script?

I am new to StackOverflow and I ended up asking this question after reading everything I could find on the Internet about captures in LPeg. I am learning LPeg and I have successfully built a few programs using captures and text substitutions using C and Cs. However I realize that there is still something escaping […]

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Mastering Development

dividing the values of data.table1 by data.table2 in R

I have created two fictional data.tables which summarise the cost and count of the items that contributed to the cost. I would like to calculate the average item cost = cost/count. How can i divide the values of the two data.tables ? combi_sum <- dcast(merge(mtcarsTOTAL[,.(cost, gear)], iris[, .N, .(carb, gear, gender, age)], by = “gear”), […]

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Mastering Development

Why Python attributes scaling function performs on previously removed attribute?

I’m scaling numerical features(attributes) in a dataset in a classifier algorithm in Data Science project. I created a list of numerical features and I pass it to a function along with the dataset, and label(class) feature all as function variables Each time I run the function; it removes the ‘label’ feature from the list, but […]

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Mastering Development

Php mysql dynamic form field value in database column

I have a form with static fields with one dynamic field. HTML <form method=”POST” action=”” name=”add_name” id=”add_name”> <div class=”form-group row”>//static fields <div class=”col-sm-4″> <input type=”text” class=”form-control” id=”asid” name=”asid” placeholder=”Enter Asset ID” required> </div> <div class=”col-sm-4″> <input type=”text” class=”form-control” id=”cost” name=”cost” placeholder=”Enter Cost”> </div> </div> <div class=”form-group row”>//dynamic field <div class=”col-sm-4″> <div id=”dynamic_field”> <input type=”text” class=”form-control” […]

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Mastering Development

I’m trying to send data to a parent table and also one of its three child tables. Only one of the child tables work and i cant figure out why

I’m using MySQL and PHP with XAMPP. I can not figure out if this is a problem with my database or with my PHP. In lines 28-96 (i made a comment in the code so you can see which ones I’m referring to) The capstone child table works. If I select capstone as the project […]

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Ask Mathematics

Bounding a solution set IVP

My general solution set turns out to be $$ c_1e^t(0,1,1)+c_2(\cos(t)-\sin(t), \cos(t), 0)+c_3(\sin(t)+\cos(t),\sin(t),0) $$ My question is what initial conditions are necessary for the solution set of the IVP $x(0)=x_{0}$ to be bounded for every $t \geq 0$? How do I go about tackling this

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Mastering Development

Sort Nested Json Object based on value in for loop?

Hoping someone can help me out here or at least point me in the right direction. I have spent hours trying to get this sorted and I am lost. The code below is just mock, my actual json is returned via AJAX using jquery. My problem is not sorting, but sorting on a nested json […]

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Development

Annotation with symbols inside stacked bar charts using Google Chart API

I have a stacked bar chart where I need to annotate the bars with $ symbol as the profit and costs are currency. I am successful in annotating of the bars without currency symbol but I am unable to display with the $ prefixed. Could anyone throw light on this <html> <head> <script type=”text/javascript” src=”https://www.gstatic.com/charts/loader.js”></script> […]

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Development

password_hash() expects parameter 2 to be long, string given [duplicate]

Since updating to php 7.4.1 I now have 2 errors appearing when people try to register. the errors are below: error 1: Warning: password_hash() expects parameter 2 to be long, string given in C:…\classes\password.php on line 31 error 2: SQLSTATE[23000]: Integrity constraint violation: 1048 Column ‘password’ cannot be null This is the code causing the […]

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Development

How to change the Hover background color in ggplotly for bar chart

I using ggplotly to plot a graph. I am using the tooltip function to represent the values in the barchart when the cursor is moved on the top of the graphs. Source_Data <- data.frame( key = c(1, 1, 1, 2, 2, 2, 3, 3, 3), Product_Name = c( “Table”, “Table”, “Chair”, “Table”, “Bed”, “Bed”, “Sofa”, […]