### Categories

### RSS Feed

### Search NewtonExcelBach

### Archives

### Top Posts

- Using LINEST for non-linear curve fitting
- Cubic Splines
- Using Goal Seek on Multiple Cells
- Commenting a block of code in VBA
- Retrieving unique values from a range or array ...
- Drawing in Excel 7 - Creating drawings from coordinates
- Getting the address of a selected range
- Arrays vs Collections vs Dictionary Objects (and Dictionary help)
- The angle between two vectors, Python version
- Solving Quadratic, Cubic, Quartic and higher order equations; examples

### Recent Comments

Alberto on 3DFrame update Using the Frame Anal… on 3D Frames, axes and stiffness… dougaj4 on 3DFrame with spring relea… cesss on 3DFrame with spring relea… Gizli on 3DFrame update dougaj4 on 3DFrame update Installing Frame4 an… on Installing C# dll files, … Installing Frame4 an… on 3DFrame update Gizli on 3DFrame update Mike on Using LinEst() on data with… dougaj4 on Using LinEst() on data with… Mike on Using LinEst() on data with… dougaj4 on Using LINEST for non-linear cu… dougaj4 on Reinforced Concrete Section An… Ahmed Moussa on Reinforced Concrete Section An…

# Category Archives: Maths

## Plotting Freeze-Thaw Data …

… or other irregular cyclic data. Another Eng-Tips question asked how to approximate ice area over a freeze-thaw cycle using a function based on a sine or cosine curve. The screen-shot below shows three alternatives: Using built in Excel functions requires … Continue reading

Posted in Arrays, Curve fitting, Excel, Maths, Newton, UDFs, VBA
Tagged cyclic data, Excel, Freeze-thaw curve, sigmoid curve, UDF, VBA
1 Comment

## Counting non-pecked chicks

Download file: Binary Chicks.zip. This post is based on a recent discussion at Cosmic Horizons looking at numerical methods to solve the following problem: The answer to the question is straightforward: With a little thought, you should be able to realise … Continue reading

## More on trend line equations on line charts

In the previous post we saw that if a trend line equation is added to a line chart it will return the wrong coefficients if the x values are not a continuous sequence of integers, starting at 1 (click on … Continue reading

Posted in Charts, Excel, Maths, Newton
Tagged chart trend line, Charts, Excel, line chart, XY chart
1 Comment

## Displaying trend line equations on line charts

This post is prompted by a recent comment at Using LINEST for non-linear curve fitting which found that the trend line formula displayed on a chart was totally different from that found using the Linest function. The problem was caused by using a … Continue reading

Posted in Charts, Charts, Excel, Maths
Tagged Chart, Excel, Show trend line equation, Trend line
Leave a comment

## Weighted Least Squares Regression, using Excel, VBA, Alglib and Python

Least squares linear regression in Excel is easy. That’s what the Linest and Trend functions do. That is, they find the coefficients of a straight line (or higher dimension shape) so that the sum of the squares of the distances of … Continue reading

Posted in AlgLib, Curve fitting, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA
Tagged AlgLib, Linest, Python, SciPy, UDF, VBA, Weighted least squares regression
Leave a comment

## On the probability of frog croaks.

A recent logical puzzle from TED discussed the probability of one of two frogs being female, if we know that at least one of them is male: This puzzle is discussed (arriving at different conclusions) here: and puzzles of this … Continue reading

Posted in Excel, Maths, Newton, VBA
Tagged croaking frog paradox, Probability puzzle, probability spreadsheet
Leave a comment

## Brent’s Method and a daft engineer’s blog

Browsing links on Brent’s Method I found: Daft Engineer – Numerical Methods and Excel* which is well worth a look (plenty of stuff on statistics and Python, with the odd dash of Excel). The link has VBA code for a … Continue reading

Posted in Excel, Maths, Newton, UDFs, VBA
Tagged Brents method, Link, Numerical methods
Leave a comment