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Oct
17
comment Newton-Raphson Method and the Van der Waal Equation Coding question
Looks like you actually want a root this time instead of the minimum. Change FindMinimum back to FindRoot. Also don't forget to adjust your PlotRange.
Oct
17
comment Newton-Raphson Method and the Van der Waal Equation Coding question
Starting conditions were found by trial and error: minimise with a starting value function, plot the results, make up a new function that approximates the good bits of the plot, repeat. See the edit for a better way to do it.
Oct
15
comment Customizing & finding intersection points in polar plot
That's why I'd like to know exactly what the theorem is. As far as I can tell, the curve does not go through equally spaced points at those angles (aside from my ability to count to eight).
Oct
14
comment Customizing & finding intersection points in polar plot
That's not a golden spiral. This might be PolarPlot[GoldenRatio^(2 n/\[Pi]), {n, 0, 2 \[Pi]}]. Can you quote or link to the theorem?
Oct
10
comment How can I speed up my numerical integration?
And should x0 be -50 or 10^-50?
Oct
9
comment How can I speed up my numerical integration?
What's x2? Also, your function f doesn't seem to use xe?
Sep
5
comment Text as plot axes values
What's the deal with Europium?
Jul
17
comment Picking numbers within a list with an interval of 60
You might need to explain a bit more clearly. For example, what's wrong with {5, 14} as one of your sublists? Posting your existing code always helps too. Split and Gather are useful functions for this type of problem.
Jun
26
comment Why doesn't FindRoot work correctly?
It's finding a root, which is all it is asked to do. Starting a bit closer might give the root that you want. Try changing your .5 to x.1.
Jun
20
comment Efficient Generation of Subgraphs (or, unfriend a friend a day)
With 10 people, they each have a choice of 9 unfriendings, giving $9^{10}$ possibilities. The next day there is probably still 10 people with 8 choices, so the total possibilities so far is $9^{10} 8^{10}$. This gets very big, very fast. I don't think you are going to brute force it.
Jun
18
comment StringReplace except some pattern
@HyperGroups Indeed. Have edited to fix.
Jun
5
comment Maintaining map dimensions after using Colorize
Why not {RGBColor[0, 0.33, 0.643], Rectangle[{-6, 41}, {-0.77, 51.5}], White, Rectangle[{-0.77, 41}, {4.47, 51.5}], RGBColor[0.98, 0.235, 0.196], Rectangle[{4.47, 41}, {9.7, 51.5}]}?
May
16
comment How to generate characters by a function which works like the Esc + a + ESC
@Mr.Wizard You're welcome to improve it. It's definitely a bit rough around the edges at the moment.
May
16
comment Generating partitions of a set with a specified size of the parts
Isn't there just one result, given by Partition[myList, 2]?
May
11
comment Prandtl-Meyer function
Looks like you might have use FindRoot to get a numerical solution (M2 -> 3.22983).
Apr
19
comment Determine the Number of Lines in a Text File
As written, the code is reading char by char. Who knows if the underlying implementation is reading in more efficient chunks? I agree that C++ I/O is a bit disappointing (and not the easiest to use either!). I might go buy a solid state drive to compensate.
Apr
18
comment Find point at which equation stops having roots (if it exists)
The help tells you how to go from the generalised incomplete gamma function to the incomplete gamma function. Then you could just evaluate the integral directly to get the rest. Or many pages (such as mathworld) give the identity for integer arguments.
Apr
17
comment Find point at which equation stops having roots (if it exists)
Or more precisely for b > 6.88164.
Apr
17
comment Find point at which equation stops having roots (if it exists)
Actually you can have roots at negative M values for b > 2.
Apr
17
comment Find point at which equation stops having roots (if it exists)
That's the message indicating that there probably isn't a root. Also, I vote for b = 2.