In the 35th session of Chandoo.org podcast, Let’s hear from Dan Fylstra, the creator of Excel Solver. I had the fortune of meeting Dan when I was in Santa Clara last month. I immediately asked him to be part of Chandoo.org podcast and he was kind enough to agree. So today let’s take a trip down the memory line, hear him talk about some of the fascinating all the early development stories of Solver, VisiCalc & Excel.

What is in this session?
In this podcast,
- Introduction
- Early days of Solver
- Working with VisiCalc, migration to Excel
- What keeps Dan busy these days
- Advice for anyone planning to learn Solver & business modelling
Listen to this session
Podcast: Play in new window | Download
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Click here to download the MP3 file.
Links & Resources mentioned in this podcast
Dan’s website:
Transcript of this session:
Download this podcast transcript [PDF]
What is your solver story?
I have learned about optimization algorithms in 2000. It has been a love-hate relationship for first several years, but then as I started my own business, I now understand how relevant modelling & optimization skills are.
What about you? What is your favourite solver story? Please share it in the comments section.
Note: Dan’s image is copyright of computerhistory.org














17 Responses to “Custom Number Formats – Colors”
You are right, Chandoo. I was playing with the colour numbers last week and some of them don't appear different from each other. Others are totally different from yours.
@Duncan
Each version of Excel, post 2003, renders colors slightly differently
Different language versions may also have different default color palettes
Hello in french
excel 2010
colo1 = couleur1 = black
[couleur1]; [couleur2]; etc..
@Hui, thank you very much again for this great post.
However - under Excel 2007, Hungarian version your solution does not work with color names. I've tried both English and Hungarian names, but drops an error message "not valid formats"
Do you have any idea how to solve this issue?
thanks in advance
@Andras
Without a Hungarian version of Excel 2003 I don't think I can assist
Have you tried using the colour numbers? I couldn't get the names to work (despite using an english version of excel). but it did work with the numbers though. I left out the "u" and was easily able to produce burgundy using [color9]
Here a possible solution: find an English version of Excel, write there the formats using English names, then open the file in the Hungarian version and see the translation.
In Excel 2007 I can't get the colour names to work e.g Sea Green but the numbers do e.g color3 - colour3 does not work so I must bow to the country that has stolen my language (ha ha!)
Hey chandoo, nice Tip!
Wouldn't be easier just apply some conditional formatting for negative numbers and another for positive numbers? Or there's some cases that you can't do that?
Unfortunately the TEXT function doesn't color the cell as number formatting does.
Hi Hui,
Great post Sir, love the new way of formatting with color numbers.
I am using 2007, and it leads me to the last color number 56.
Thanks Hui.
[…] explains how to set up custom number formats with a wide array of […]
Thanks Hui - works a treat!
Thank you, very helpful.
Trying to figure out if it is possible to apply color only to a part of the cell?
E.g. I have a value formatted as Accounting with a currency symbol.
Those I find somewhat distracting though necessary. If I could make them less obtrusive by coloring them gray while the number would stay black, that would be great. Tried tinkering with the format string, but didn't get the desired result. Single color for complete cell value works, but coloring just part of it could not be achieved. Maybe somebody managed that?
Exactly what I was looking for - thank you!
colour in the Australian doesn't work - we have to go American and no problem.
I always thought is was 56 colours notice you have 57. Cool.
thanks
Analir Pisani
Customised Microsoft Office Training Specialist
Sydney - Australia
http://www.azsolutions.com.au
Thank You!