Logarithmic Scale Base

[soubasa]

Hello, In chart Logarithmic Scale Base shows "Enter a Number from 2 to 1000", It means 2x up to 1000x :

such as : when base is 2 and base number is 1000 then shows 2000 - 4000 - 8000 - 16000 - ... doubles down

when base is 10 and base number is 1000 then shows 10000 - 100000 - 1000000 - 10000000 - ... tenfold increase

now I need Logarithmic Scale show me less than 2x

such as : base number could be show "0.2" in the case of base number is 1000 then show : 1200 - 1440 - 1728 - 2073

etc ...

in arithmetic chart is not problem but in logarithmic This restriction is annoying

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Is this Excel behavior changeable or can a trick be used?

Thanks for your advice.

[MrShorty]

To my knowledge, there is not a built in way to use a non-integer base for the built in logarithmic axis.

The "trick" I would use would be to plot the desired logarithms (=LOG(number,1.2)), then use a technique like this to fake my own logarithmic axis:
The technique being used to create a reciprocal horizontal axis: https://peltiertech.com/reciprocal-chart-axis-scale/
The technique being used on a base 10 log axis to get different text for the axis labels: https://peltiertech.com/Excel/Charts...cNotation.html

[soubasa]

Hello again
sorry for delay
could you please show me on attach file?
thank you very much

[swaatacba]

I'm not quite sure what you are looking for, but I have re-arranged your values in col B as values under log to the base 2, 0.5, 5 and 0.2 respectively.

Personally, for decimal numbers close to 1, I would stick with them.

[soubasa]

Hello
thank you for your time
actually I need to see more number in log scale price column
I understand what means of logarithmic scale, infact my price range from bottom to top of range is less than base 2 maybe less than 1.1 and I can't see more number
I need some "tricks, fake lable" or anything else to show me price in column when I use of log scale
please look at my picture that I attached
thank you very much

[swaatacba]

Excel will not allow you to plot negative logarithmic values. Given your range of data you will always get some. It appears that the logarithmic approach is a non-starter.

[soubasa]

Is there any way to use logarithmic scale on vertical (value) axis less than base 2?
tricks , manual data lable , fake lable or anything else can help me
thanks

[MrShorty]

I won't be able to look at this closer until later. Are there specific parts of Peltier's tutorials that you have difficulty implementing? I would expect:

1) In a convenient place in the spreadsheet, enter a column of 0s (X values for new, xy scatter data series), a column for the desired data label values, and a column with the desired logarithm of those values (LOG() function -- y values for new, xy scatter data series).
2) Go into the Select data dialog and add a new data series, use the column of new y values for the values.
3) Change this new data series to an xy scatter chart type (to create the line + xy scatter combination chart). Excel may automatically add secondary vertical and horizontal axes.
4) From Select Data dialog, edit the new data series to use the correct x values for this data series (the column of 0s from step 1).
5) Come up with a workable combination of scale on the secondary horizontal axis and value in the x values that correctly positions the xy scatter data series on top of the primary vertical axis.
6) Add data labels (values from cells option) to the xy scatter data series and tell it to use the data label values column from step 1.

[swaatacba]

This chart shows a possible logarithmic approach (in brown) and compares it with your original (in blue). I do not think the logarithmic way forwarLog Scale.pngd is helpful.

[MrShorty]

Here's a file starting from your sample file in post #3 and following the steps I outlined in post #8. My older version doesn't support data labels from cells, so you will need to format the data labels to do that.

[soubasa]

Hello
Due to the Excel file I need calcualte logarithmic percent in arithmetic situations
please look at my file I explaint completely in the file

maybe my question be hectic but when you see my file you will understand my mean


Thank you in advance

[Glenn Kennedy]

There is NO explanation in the file at all! Did you attach the correct file?

[AliGW]

The duplicate thread has been closed and posts copied here - you may update the title of the opening post, if you wish.

[soubasa]

actually I need label for logarithmic price column in line chart
I can create shape lable for column if I have logarithmic price in column

[MrShorty]

I agree that the explanation, if present, is at best incomplete.

I see a formula for Ca (Ca being the arithmetic version, the values in row 4) -- Ca=B-x*(B-A) where x is the values in C2:F2.
I see a formula for Cl (Cl being the logarithmec version, the errors in row 8) -- log(Cl)=log(B)-y*(log(B/A)) where y would be the values in C6:F6.

My guess is that you want to find the values for y that make Ca=Cl. If so, I find that I would prefer to solve this first as an algebra problem, then I will be better able to program the appropriate formulas in the spreadsheet.

Am I guessing right at what you are trying to do?

[soubasa]

I agree that the explanation, if present, is at best incomplete.

I see a formula for Ca (Ca being the arithmetic version, the values in row 4) -- Ca=B-x*(B-A) where x is the values in C2:F2.
I see a formula for Cl (Cl being the logarithmec version, the errors in row 8) -- log(Cl)=log(B)-y*(log(B/A)) where y would be the values in C6:F6.

My guess is that you want to find the values for y that make Ca=Cl. If so, I find that I would prefer to solve this first as an algebra problem, then I will be better able to program the appropriate formulas in the spreadsheet.

Am I guessing right at what you are trying to do?

Hello, first of all, thank you for your composure in answering
In the PDF file that I attached in this post I explained completely my request
In this pdf, I tried with all my might to convey my meaning in a comprehensive way, I hope that I have succeeded in this way

Thank you for your time

[MrShorty]

The question on page 3 (how to add labels to the vertical chart axis) should be already answered. I gave an outline of the procedures needed in post #8 and a sample file in post #10. What parts of my description and sample are not clear? Or have I misunderstood what you want and this does not accomplish your goal?

I must not be understanding what you want to do with the rest. It still looks to me like you want to set arithmetic to logarithmic and find the percentage multiplier (y in my algebraic breakdown) that makes logarithmic (Cl in my algebraic breakdown) the same as arithmetic (Ca in my algebraic breakdown). But you seem to have rejected that description, so I am not sure exactly what you are wanting from this part of the analysis.

If it helps, setting Cl to Ca as I proposed and solving for y, I get y=0.1926 when x=0.25, y=0.415 when x=0.5, and y=0.678 when x=0.75. Are those values correct?

I couldn't find anything on neowave's website that explains the analysis you are trying to perform.

[soubasa]

Hello
for your last paragraph "If it helps, setting Cl to Ca as I proposed and solving for y, I get y=0.1926 when x=0.25, y=0.415 when x=0.5, and y=0.678 when x=0.75. Are those values correct?" YES
could you please send me your formula to calculate it?
Thank you for your time

Please accept my deepest thanks

[MrShorty]

As I said earlier, it is more algebra than Excel programming.

Start by setting Ca=Cl (or, easier, Log(Ca)=Log(Cl)). Substitute.
Log(Ca)=Log(Cl) -> Log(B-x*(B-A))=Log(B)-y*(Log(B/A)). Solve for y.
Subtract Log(B) from both sides and divide both sides by -Log(B/A)
y=(Log(B-x*(B-A))-Log(B))/-Log(B/A)
If desired, I'm sure that can be further simplified by following the rules for manipulating logarithms, but I opted to end there.

Enter that formula into C6 (with an appropriate mix of relative and absolute references) and copy/paste/fill into C6:F6.