Plotting with 2 y axes

My data is the following:




Time

Resistance

Temperature


5

2000

4


10

2200

8


15

2500

14


20

2900

20


25

3000

29


30

3100

38


35

3500

46


40

3800

47


45

3900

50


50

4000

51



I would like to create a scatter plot with Time on the x axis, Resistance on
the y axis and Temperature on a second y axis.



I have tried

Plot(Time,Resistance,ylim=range(0,4500)

Points(Time,Temperature)

Axis(side=4)



But the temperature ends up as a straight line along the bottom.  I also
tried

plot(time, resistance, ylim=c(0,4500), col="black", type="b") points(time,
4500/60 * temperature, col="green", type="b") axis(side=4,
at=4500/60*seq(0,60, by=10), labels=seq(0,60,by=10))



but that just scales temperature appropriately to match the Resistance and
does not plot off of a second y axis.  I have many plots to create and need
resistance plotted on one y axis and Temperature plotted on the second.



Thanks in advance, keith





Marlin Keith Cox Ph.D.

At-Sea Processor Professorship of Fisheries Biology
Science Chair

Sheldon Jackson College

Sitka, Alaska 99835

907.747.5296

http://www.sheldonjackson.edu




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