MAT1 = matrix(c(1,2,3,2,5,6,3,6,9),nrow = 3, ncol = 3, byrow = FALSE)
MAT2 = matrix(c(1,0,0,0,1,0,0,0,1),nrow = 3, ncol = 3, byrow = FALSE)
MAT1 + t(MAT1)
## [,1] [,2] [,3]
## [1,] 2 4 6
## [2,] 4 10 12
## [3,] 6 12 18
MAT1 - t(MAT1)
## [,1] [,2] [,3]
## [1,] 0 0 0
## [2,] 0 0 0
## [3,] 0 0 0
MAT1 * MAT2
## [,1] [,2] [,3]
## [1,] 1 0 0
## [2,] 0 5 0
## [3,] 0 0 9
(t(MAT1) + MAT2)*(MAT1 + MAT2)^-1
## [,1] [,2] [,3]
## [1,] 1 1 1
## [2,] 1 1 1
## [3,] 1 1 1
B0 = -.34
B1 = 1.04
X1 = seq(0, 0+3, by=.001)
e = exp(1)
LOG1 = log(B1)*X1
plot(B0 + B1*X1^2)
plot(B1*e^X1)
plot(B0 + e^(B1*X1))
plot(B0+e^LOG1)
url <- "ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_annmean_mlo.txt"
DFCO2 <- read.table(url,header=FALSE)
## Warning in file(file, "rt"): the 'wininet' method of url() is deprecated for
## ftp:// URLs
colnames(DFCO2) <- c("year","meanCO2","unc")
CO2LM = lm(DFCO2$meanCO2~DFCO2$year)
summary(CO2LM)
##
## Call:
## lm(formula = DFCO2$meanCO2 ~ DFCO2$year)
##
## Residuals:
## Min 1Q Median 3Q Max
## -4.971 -2.904 -1.323 2.523 9.073
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) -2.855e+03 5.496e+01 -51.94 <2e-16 ***
## DFCO2$year 1.614e+00 2.762e-02 58.45 <2e-16 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 3.986 on 61 degrees of freedom
## Multiple R-squared: 0.9825, Adjusted R-squared: 0.9822
## F-statistic: 3416 on 1 and 61 DF, p-value: < 2.2e-16
Y2 = DFCO2$meanCO2
X2 = DFCO2$year
X3 = matrix(,
nrow = 63,
ncol = 3)
X3[,1] = 1
X3[,2] = seq(1959, 1959+62, by=1)
X3[,3] = seq(1959, 1959+62, by=1)^2
Y2MEAN = mean(DFCO2$meanCO2)
ABSDIS = sum(abs(Y2-Y2MEAN))
SQRDIS = sum((Y2 -Y2MEAN)^2)
plot(x = DFCO2$year,y = DFCO2$meanCO2, xlab = "Year", ylab = expression("Mean annual "*CO[2]*" concentration"), main="CO2 each year",col="blue",abline(CO2LM))
