# How to Create a Spreading Double Helix Image in Excel

Learn to make the "Spreading Double Helix" image below by either modifying a workbook from a previous article and/or following the steps here laid out, plus gain access to the dozens of variations possible.

## Steps

• Become familiar with the basic image to be created: ### Part 1 The Tutorial

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This workbook is the direct child of the article #03 How to Create a Tornado Screw Pattern in Microsoft Excel, so you can Save As your workbook from that article and retitle it appropriately, and follow the steps, watching for NEW and/or MODIFIED notes where change have occurred .... or, you can simply construct the file from scratch by following the steps completely from the previous articles for #01 How to Create Artistic Patterns in Microsoft Excel and #02 How to Create a Flower Pattern in Microsoft Excel first. Beginning at Step 2 then, this is a direct copy of How to Create a Tornado Screw Pattern in Microsoft Excel, except where NEW changes or MODIFICATIONS have occurred, except for the last step or so concerning creating the chart of course. Since #03 depended on #01 and #02, it is expected that those have been completed.
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If you've opted to, start a new workbook by saving the old workbook (from How to Create a Flower Pattern in Microsoft Excel) under a new name. Save the workbook into a logical file folder.
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Insert a new column at Column A. Enter "=ROUND(1440/S_COUNT,1)" into cell A1. Format Cell Number Number Custom "Rrs" 0. Insert Name Define name Rrs to cell \$A\$1.
• Enter the formula "=ROUND(1440/Rrs,0)" into cell A2.
• Enter On=0,Off=1 into cell A3.
• Enter 1 into cell A4.
• Edit Go To cell range A7:A1447 and with A7 active, enter the formula without quotes "=IF(OR( AND((ROW()-7)>Rrs,(ROW()-7)<=Rrs*2), AND((ROW()-7)>Rrs*4,(ROW()-7 <=Rrs*5), AND((ROW()-7)>Rrs*7,(ROW()-7)<=Rrs*8), AND((ROW()-7)>Rrs*10,(ROW()-7)<=Rrs*11), AND((ROW()-7)>Rrs*13,(ROW()-7)<=Rrs*14), AND((ROW()-7)>Rrs*16,(ROW()-7)<=Rrs*17), AND((ROW()-7)>Rrs*19,(ROW()-7)<=Rrs*20), AND((ROW()-7)>Rrs*22,(ROW()-7)<=Rrs*23), AND((ROW()-7)>Rrs*25,(ROW()-7)
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MODIFIED: Insert Name Define Name Divisor into cell \$E\$3 and enter -1000. Format Cell Fill Yellow Font bold and Number Number Custom "Divisor" 0.00 with quotes.
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Insert Name Define Name AAA into cell \$D\$5 and enter.000004. Format Cell Fill Yellow Font bold and Number Number Custom "AAA" +.00000000;"AAA" -.00000000 with quotes.
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MODIFIED: Enter 12 into cell B2, TURNS. Enter 38.5 into S's Count cell C1 for Spheroids (the example chart uses38.5 but the pairs come out better with 24 perhaps). Enter 968277 into cell D3, top. Enter .61 into cell H1 and .78 into cell J1. The variable Sync1 in H2 is "=H1/GMLL" and the variable Sync2 in J2 is "=J1/GMSL"
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Check the formulas in the columns:
• MODIFIED: B7: "=IF(EVEN(S_COUNT)=S_COUNT,ROUND((-B4*PI())+(Adj),0),TOP)" w/o quotes for this and all of this step's formulas. Adj in B5 has the formula "=IF(TURNS>0,VLOOKUP(TURNS,TURNS_LOOKUP,2),VLOOKUP(TURNS, TURNS_LOOKUP_NEG,2))" and = 352. TOP = "=ROUND((-B4*PI())+(Adj),0)" where B4 = -308.100 in cell B4. So TOP = 968,277.
• MODIFIED: C7: "=ROUND(-EXP((PI()^2)+(Cc*-(db))),0)+Designer" Cc "=-0.25*PI()/C3" where C3=12, db = 4.5 and Designer = 9810.
• C8:C1447: "=C7"
• NEW/MODIFIED: D7:D1447: "=IF(A7=0,D6,COS((ROW()-7)*Factor*PI()/(180))*((ROW()-7)/Divisor))" Factor = .385 and Divisor = -1000.
• NEW/MODIFIED: E7:E1447: "=IF(A7=0,E6,DEGREES((ROW()-7))/41500)" This uses the DEGREES() function for the first time. See Tips for #03 and Excel Help under Home > Function References > Math and Trigonometry Functions.
• NEW: F7:F1447: "=IF(A7=0,F6,((PI())*((SIN(B7/(C7*2))*GMLL*COS(B7)*GMLL*(COS(B7/(C7*2)))*GMLL)+D7)))". For F6, the new header reads Dbl Helix x.
• NEW: G7:G1447: "=IF(A7=0,G6,((PI())*((SIN(B7/(C7*2))*GMLL*SIN(B7)*GMLL*(COS(B7/(C7*2)))*GMLL)+E7)))". For G6, the new header reads Dbl Helix y.
• NEW: H7:H1447: "=2+(F7*-1)" and the new header for H6 is 2nd Helix x.
• NEW: I7:I1447: ""=G7" and the new header for I6 is 2nd Helix y.
• J7:J1447: "=F7*GMSL*Sync2" (this is no longer charted however)
• K7:K1447: "=G7*GMSL*Sync2" (this is no longer charted however)
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The various Lookup Tables have not changed since "Create Special Designs and Patterns 02". Here below are images of the header rows and data to check against. There should be no errors. Make sure there is a formula in cell A7.

### Part 2 Explanatory Charts, Diagrams, Photos

• (dependent upon the tutorial data above)
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The charting is as follows: 1) Edit Go To cell range F7:G1446 and do Charts on the Ribbon, All/Other and scroll down to Scattered - Smoothed Line Scatter. Copy or cut the chart that appears atop the data and paste to the Charts worksheet; 2) Tap in the Plot Area and above select Chart Layout and get rid of Axes, Legend and Gridlines; 3) At left, select under Current Selection Series 1 and under that choose Format Selection and do Line Color Blue, Smoothed Line, Line Weight 1; 4) Tap again in the Plot Area and select menuitem Chart, Add Data and respond to the query by selecting on the Data worksheet cell range H7:I1446, which may come out wrong and you may have to edit the data series in the Chart worksheet;s formula bar to read "=SERIES(,Data!\$H\$7:\$H\$1446,Data!\$I\$7:\$I\$1446,2)"; 5) Do Format Selection under Chart Layout again by tapping in the Plot Area and select Data Series 2 and do Line Color Red, Smoothed Line, Line Weight 1; 6) Format Selection Plot Area and from the Color Wheel select Sky Blue or bright Turquoise Blue for the Fill.
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Finished!

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Make use of helper articles when proceeding through this tutorial:

## Tips

• S_Count=24, On or Off = 0:
• After adding new variable Multiplier w/ a value of 0.000005 and adjusting column D and E formulas to read "=IF(A2869=0,D2868,COS((ROW()-7)*Factor*PI()/(180))*((ROW()-7)/Divisor))/1.5" and "=IF(A2869=0,E2868,DEGREES((ROW()-7))/(41500+Multiplier*ROW()))", respectively, the following alignment was obtained for S_COUNT 38.5:  <br ## Warnings

• ERRORS: If there are errors or error values, either the sheet in incomplete and needs further input or Lookup Tables for critical variables or perhaps there's a mistake somewhere along the line. If the instructions have been completed and there are still errors, select the cell that has the error value that is furthest left and topmost first. Look for a typo in a formula or unmatched parentheses. Possibly, a Defined Name is wrong -- they need to be input into the formulas exactly as they were defined. Do Insert Name Define to check. If there is a #DIV/0! error, the example does not, so look for a variable that somehow did not get filled in with a value perhaps. At any rate, what to do is select the cell with the error, and after checking all those typical errors, do Tools Auditing Trace Precedents and/or Trace Error. If fixing all the topmost leftmost errors does not fix the rest of your errors on the worksheet, one may need to do it the hard way, from the bottom right upwards then leftwards; that is the slow but sure way to fix all errors.
• Also, errors in the chart data will most likely plot as zeroes. This may be acceptable or desirable even. However, if too many lines (or curves) are returning to 0, it may indicate a logical flaw in the data -- or too many tiny values and then perhaps rescaling the chart is needed by inspecting the horizontal and vertical axes and changing them to zero in on the problem. Hover over or click on a data marker on the series plot and then do a search in the proper column by value for that value, and identify its precedents.

## Sources and Citations

• The source workbooks for this article are "Garthwaite Line06.xlsx" and "Garthwaite Line06c.xlsx".

## Article Info

Categories: Microsoft Excel Imagery | Mathematics