Dec 082013


UCL Department of Mathematics

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 Posted by at 11:22 am
May 292013

Re: HP PRIME GRAPHING CALCULATOR – Technical data and performance comparison with others.

a month ago



I think it’s important to precise that all of this is absolutely not official.

Perhaps these specs are true. Perhaps not … At this stage, it’s only rumors. The only official annoncement is the video and noting on specs inside.





Honored Contributor
Posts: 2,160
Registered: ‎02-09-2009
Message 3 of 11 (2,027 Views)

Re: HP PRIME GRAPHING CALCULATOR – Technical data and performance comparison with others.

[ Edited ]

a month ago – last edited a month ago

Hi!, all:


The first program, of Fractals, for HP PRIME GRAPHING CALCULATOR, from …


LOCAL iter := 0;
LOCAL z := (0,0);
WHILE (ABS(z) <= bailoutValue) AND (iter < maxIter) DO
z := z*z+c;
iter := iter+1;
RETURN iter;

Ndx := ROUND(Ndx*186,0);
IF Ndx < 31 THEN RETURN 0+ 1*Ndx; END;
IF Ndx < 62 THEN RETURN 31+ 32*(Ndx-31); END;
IF Ndx < 93 THEN RETURN 1023- 1*(Ndx-62); END;
IF Ndx < 124 THEN RETURN 992+ 1024*(Ndx-93); END;
IF Ndx < 155 THEN RETURN 32736- 32*(Ndx-124); END;
IF Ndx < 186 THEN RETURN 31744+ 1*(Ndx-155); END;
RETURN 31775;

colorize(itVal, maxIt)
IF itVal==maxIt THEN
// We are inside the Mandelbrot map
// Then the pixel is drawn in blackRETURN 0;
RETURN LSclr(itVal/maxIt);

EXPORT Mandelbrot()
// Clean the screen (G0):RECT();

LOCAL dx, dy, c, xp, yp;
LOCAL iter, color;

// These 4 variables defined
// Our window of the complex plane

LOCAL xmin, xmax, ymin, ymax;
LOCAL maxIterations := 50;
LOCAL maxRadius := 2;

// Location
// Radio width to height should be 4:3

xmin := -2.5;
xmax := 1.5;
ymin := -1.5;
ymax := 1.5;

// Other parameters better:

//xmin := 0.315625;
//xmax := 0.515625;
//ymin := 0.28125;
//ymax := 0.43125;

dx := (xmax-xmin)/320;
dy := (ymax-ymin)/240;
c := (xmin,ymin);

// we loop over each pixel
// Of the screen wil Prime:
FOR yp FROM 0 TO 239 DO
FOR xp FROM 0 TO 319 DO
// Create the complex number c
// We need for iteration:

c := (xmin+xp*dx, ymax-yp*dy);

// Now iterate the formula and
// Return the number of iteration steps
// That was taken up
// That the complex number jump out
// The radius of convergence:

iter := iteration(c, maxRadius, maxIterations);

// Determines a color for the iteration number:color := colorize(iter, maxIterations);

// Change color to that pixel:

PIXON_P(xp, yp, color);

// deja la imagen en la pantalla
// hasta que se presiona una tecla:



if you consider … click the KUDOS Star, on the left, to show appreciation, or Thanks.
Best Regards.

 Posted by at 8:44 pm
May 252013

Online Algebra Calculator

Many of users do not use powerful Maxima computer algebra system for systematic work, but for ad hoc algebraic calculations – equations, functions, matrixes, etc. only. To do this job, it is not useful to download the whole application from a web site.

Sponsored links: Mathematics eBooks
 Posted by at 4:38 pm
Apr 012013

Home Services Gallery FAQ HowTo Support

Sample applications

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webMathematica 2.0.

From this page you can navigate to examples of webMathematica, browse the documentation, and learn more from the Wolfram Research web site. Wolfram Research wrote these as examples of good design and good programming practice. Please use the code as a template for your own work.

webMathematica is a unique technology for creating web sites that allow users to compute and visualize results directly from a web browser.

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© 2003

 Posted by at 5:43 am
Mar 212013

What’s New

Part 1: Average and Standard Deviation
by Mark Lawrence

Neural Networks

What’s New

Mark’s Market Blog
Blog Table of Contents

Investing 101
Bank Accounts
Real Estate
Natural Resources
Stock Indexes
Portfolios & Risk
Mutual Funds
Index Funds

Normal Distributions
Standard Deviation
Covariance Matrix

What is money?
Interest and Growth
Money Utility and Risk
Trade Deficits and Inflation
Distribution of Income
Home Ownership
Distribution of Wealth

Simple Interest
Compounding Interest
Zero Coupon Bonds
Government Bonds
Industry Bonds
Bond Funds
Bond Ladders
Reading Bond Pages
Calculating Interest

Advanced Topics

Risk & Volatility
QPR Trusts

About This Site

I recommend FireFox

People come in lots of different heights. Let’s think about the height of American men.

The average American man is 5’10”. This means half of all American men are taller than 5’10”, and half are shorter than 5’10”. This one fact does not tell us much about how height is distributed, however. One could ask what’s the tallest American man? The shortest? How many men are over 6’6″? Suppose you measured the height of a hundred men chosen at random off the street. You would most likely measure something much like the following table:

Measuring the height of 100 American men
Graph: gaussian
Height 5’3″ 5’4″ 5’5″ 5’6″ 5’7″ 5’8″ 5’9″ 5’10” 5’11” 6′ 6’1″ 6’2″ 6’3″ 6’4″
Count 1 3 4 6 7 12 17 17 12 7 6 4 3 1

It turns

Neural Networks

 Posted by at 7:20 pm
Mar 142013

Help your memory:

Dej o Boze o mocny pamatovat si takovy cifer rad, velky slovutny Archimede, pomahej trapenemu, dej mu moc, nazpamet necht odrika ty slavne sice, ale tak protivne nam ty cislice Ludolfovy

3,14159 26535 89793 23846 26433 83279


Dej ó Bože ó mocný pamatovat si takový cifer řád, velký slovutný Archimede, pomáhej trápenému, dej mu moc, nazpaměť nechť odříká ty slavné sice, ale tak protivné nám ty číslice Ludolfovy

3,14159 26535 89793 23846 26433 83279


 Posted by at 8:14 pm
Mar 052013
Mathematics of Computation
Mathematics of Computation
ISSN 1088-6842(online) ISSN 0025-5718(print)


An algorithm for computing logarithms and arctangents

Author: B. C. Carlson
Journal: Math. Comp. 26 (1972), 543-549
MSC: Primary 65D20
MathSciNet review: 0307438
Full-text PDF Free Access

Abstract | References | Similar Articles | Additional Information

Abstract: An iterative algorithm with fast convergence can be used to compute logarithms, inverse circular functions, or inverse hyperbolic functions according to the choice of initial conditions. Only rational operations and square roots are required. The method consists in adding an auxiliary recurrence relation to Borchardt’s algorithm to speed the convergence.

 Posted by at 7:14 am
Mar 052013

AGM method

From Wikipedia, the free encyclopedia
Jump to: navigation, search
It has been suggested that this article or section be merged into arithmetic–geometric mean. (Discuss) Proposed since September 2012.

In mathematics, the AGM method (for arithmetic–geometric mean) makes it possible to construct fast algorithms for calculation of exponential and trigonometric functions, and some mathematical constants and in particular, to quickly compute \pi.

 Posted by at 7:12 am
Feb 142013

Go to EXCELENT tool – js emulator (thanks to F. Bellard)


sw modem

Help, tutorials …




ls -al (list)


dmseg | more




 Posted by at 8:04 pm
Feb 032013

Experimental Mathematics Website

<== This is a picture from the interactive geometry package Cinderella showing the behavior of 10,000 starting values in the rectangle [0,1]x[h-1,h+1], where h is the height of the horizontal line, after six iterations of the algorithm which reflects a point x in the sphere then reflects the outcome in the line and then averages the result y with x. It is an accessible prototype for a remarkable image reconstruction algorithm known variously as Douglas-Ratchford, Lion-Mercier, Fienup’s method, and “divide-and-concur.” Some related graphics can be generated and displayed at these URLs: Expansion Reflection (wait 30-60 seconds to see the display).

Quote of the day (refresh browser to select another): We [Kaplansky and Halmos] share a philosophy about linear algebra: we think basis-free, we write basis-free, but when the chips are down we close the office door and compute with matrices like fury. — Irving Kaplansky (1917-2006), quoted in John H. Ewing and F.W. Gehring, ed., Paul Halmos: Celebrating 50 Years of Mathematics, Springer, 1991.

The complete list of quotes is available here.

This website is a repository of information on experimental and computer-assisted mathematics. It is operated by


  • David H. Bailey, Lawrence Berkeley Laboratory, Berkeley, California (DHB website)
  • Jonathan M. Borwein, University of Newcastle, Newcastle, Australia (JMB website)

 Posted by at 7:58 am
Feb 012013

vypocty.txt · Poslední úprava: 2013/01/19 11:29 (upraveno mimo DokuWiki)

 Posted by at 9:08 pm
Jan 292013


GNU Octave is a high-level interpreted language, primarily intended for numerical computations. It provides capabilities for the numerical solution of linear and nonlinear problems, and for performing other numerical experiments. It also provides extensive graphics capabilities for data visualization and manipulation. Octave is normally used through its interactive command line interface, but it can also be used to write non-interactive programs. The Octave language is quite similar to Matlab so that most programs are easily portable.

Octave is distributed under the terms of the GNU General Public License.


January 28, 2013
OctConf 2013 will take place in Milano, Italy during June 24-26, 2013. All Octave users, developers, and enthusiasts are welcome to attend!
August 1, 2012
ESA approved two students to work for Octave under the SOCIS mentorship programme! Congratulations to Wendy Liu and Andrius Sutas who will be working on finishing the Agora website and low-level I/O respectively.
July 18, 2012
Octave has been accepted into SOCIS. We’re now hiring for one position!
July 16, 2012
OctConf 2012 is currently underway.
June 8, 2012
Planet Octave is up, which is a collection of blogs related to Octave. At the moment, it’s principally dedicated to the blogs from students working under Google Summer of Code.
May 31, 2012
Version 3.6.2 has been released and is now available for download. Octave 3.6.2 is a minor bug-fixing release. See the NEWS file for a list of user-visible changes since 3.4.

For older news, see the news archive.

 Posted by at 8:51 pm
Jan 062013

This Week’s FindsLatest Edition       Fun Stuff     Nasty Stuff     Serious Stuff     Talks     Seminar     Diary     Azimuth Blog      Azimuth Project      n-Category Café      nLab      EUREKA      Physics FAQ    


Search the web Search my webpages

John Baez’s Stuff

I’m a mathematical physicist. I’m at the math department at U. C. Riverside, but in the summer I work at the Centre for Quantum Technologies in Singapore. I’m working on information geometry, network theory, and the Azimuth Project, which is a way for scientists, engineers and mathematicians to do something about the global ecological crisis. If you want to help save the planet, please send me an email or say hi on my blog.

What’s New?

Read my series on the mathematical delights of rolling circles and balls!


Learn about Platonic solids, Coxeter complexes and Coxeter diagrams in this series of posts: part 1, part 2, part 3, part 4, part 5, part 6, part 7 and part 8. Here’s the Coxeter complex for the symmetry group of a dodecahedron:


Learn about our galactic environment. What will happen when our solar system hits the next big cloud of interstellar gas?


Listen to my new piece called Shimmer:


See my American Geophysical Union talk:


It’s an introduction to a project you can join, which is all about environmental problems and how to solve them. Click the links for more details. Or, watch my related talk about The Mathematics of Planet Earth.

Learn about infinities called countable ordinals—big ones and bigger ones!—here on Google Plus.

The tallest mountain in the world is Sāgārmatha, also known as Chomolungma. But to reach it from the southeast, as most climbers do, you must pass Khumbu Icefall and Valley of Silence. Read about them in my blog.


Or if you prefer math to mountains:


There’s a math puzzle whose answer is a really huge number. How huge? According to Harvey Friedman, it’s incomprehensibly huge. Now Friedman is an expert on enormous infinite numbers and how their existence affects ordinary math. So when he says a finite number is incomprehensibly huge, that’s scary. It’s like seeing a seasoned tiger hunter running through the jungle with his shotgun, yelling “Help! It’s a giant ant!” For more, read this.


In week319 of This Week’s Finds, learn about catastrophe theory in climate physics! This is the first issue that features a program you can play with on your browser. It’s a simple climate model that illustrates how a small increase in the amount of sunlight hitting the Earth could have a big effects on the climate, by melting snow and revealing darker soil. It was made by Allan Erskine.

Also on my blog, learn about ice, its many forms and crystal structures, how it resembles diamonds, and what scientists do with a machine that uses 80 times the world’s electrical power for the few nanoseconds it’s running.


If you like astronomy, read about the moon called Dysnomia, a planet whose atmosphere liquifies and then freezes every year, the reason so many objects in the outer solar system are red, why the same chemicals you find in the tarry buildup on a barbecue grill are also seen in outer space… and whether life on Earth could have been started by complex compounds from comets!


If you like art, check out some photos from my trip to Chiang Mai in Thailand:


Archimedean tilings are beautiful patterns whose possibility is predicted — but not guaranteed — by solutions to a simple equation. I’ll explain what that equation says, where it comes from, and what happens when things don’t quite work!


If you plot all the roots of polynomials whose coefficients are 1 and -1, say polynomials of some large degree like 24, you get a picture like this:


How can we understand the amazing patterns here? Read The Beauty of Roots for some answers!



What’s on This Site

Also try my blog at:

For common questions about physics, you can’t beat this:

I don’t maintain this Physics FAQ – Don Koks does, so please send any comments about it to him, not me!

If reading my stuff makes you want to ask questions, take a look at this.



The universe is full of magical things, patiently waiting for our wits to grow sharper. – Eden Philpotts

© 2011 John Baez

 Posted by at 6:26 am
Sep 232012

Excel's NORM.S.DIST function translates standard deviations (z) into cumulative probabilities.

An Introduction to Excel’s
Normal Distribution Functions

Excel provides several spreadsheet functions for working with normal distributions or “bell-shaped curves.” Here’s an introduction for people who are statistically challenged. Also, you’ll find two ways to calculate a random number from a normal distribution.

Microsoft Excel MVP by Charley Kyd, MBA
Microsoft Excel MVP
 Posted by at 1:26 pm