Running examples in 'sensitivity-Ex.R' failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: morris
> ### Title: Morris's Elementary Effects Screening Method
> ### Aliases: morris tell.morris print.morris plot.morris plot3d.morris
> ### Keywords: design
> 
> ### ** Examples
> 
> # Test case : the non-monotonic function of Morris
> x <- morris(model = morris.fun, factors = 20, r = 4,
+             design = list(type = "oat", levels = 5, grid.jump = 3))
> print(x)

Call:
morris(model = morris.fun, factors = 20, r = 4, design = list(type = "oat",     levels = 5, grid.jump = 3))

Model runs: 84 
              mu    mu.star      sigma
X1   -3.52143445  92.799934 134.566290
X2  -89.60445040  89.604450  79.479469
X3   16.41961903  16.419619  14.832555
X4   -5.44297158  92.098448 109.394619
X5   55.50961217 107.814607 128.539754
X6   49.00986039  53.962467  60.109622
X7   40.35992063  40.359921  33.065078
X8   46.63644916  46.636449  10.138739
X9   36.71189292  36.711893   5.964791
X10  42.81802916  42.818029   1.444105
X11   3.69045491   6.652880   8.472518
X12  -1.84780875   3.909518   4.510390
X13   5.53530441   7.365032   7.213616
X14  -1.42213634   3.685281   4.402491
X15  10.39970810  10.399708   4.758055
X16  -2.94227959   7.785707   9.698142
X17   2.14226347   3.718695   4.284666
X18   1.91094561   6.201033   7.121521
X19  -5.37366503   5.373665   4.663188
X20  -0.03740253   7.608779   9.533040
> plot(x)
> 
> # Only for demonstration purposes: a model function returning a matrix
> morris.fun_matrix <- function(X){
+   res_vector <- morris.fun(X)
+   cbind(res_vector, 2 * res_vector)
+ }
> x <- morris(model = morris.fun_matrix, factors = 20, r = 4,
+             design = list(type = "oat", levels = 5, grid.jump = 3))
 ----------- FAILURE REPORT -------------- 
 --- failure: the condition has length > 1 ---
 --- srcref --- 
: 
 --- package (from environment) --- 
sensitivity
 --- call from context --- 
ee.oat(X, y)
 --- call from argument --- 
if (class(y) == "numeric") {
    one_i_vector <- function(i) {
        j <- ind.rep(i, p)
        j1 <- j[1:p]
        j2 <- j[2:(p + 1)]
        return(solve(X[j2, ] - X[j1, ], y[j2] - y[j1]))
    }
    ee <- vapply(1:r, one_i_vector, FUN.VALUE = numeric(p))
    ee <- t(ee)
} else if (class(y) == "matrix") {
    one_i_matrix <- function(i) {
        j <- ind.rep(i, p)
        j1 <- j[1:p]
        j2 <- j[2:(p + 1)]
        return(solve(X[j2, ] - X[j1, ], y[j2, , drop = FALSE] - 
            y[j1, , drop = FALSE]))
    }
    ee <- vapply(1:r, one_i_matrix, FUN.VALUE = matrix(0, nrow = p, 
        ncol = ncol(y)))
    if (p == 1 && ncol(y) == 1) {
        ee <- array(ee, dim = c(r, 1, 1))
    }
    ee <- aperm(ee, perm = c(3, 1, 2))
} else if (class(y) == "array") {
    one_i_array <- function(i) {
        j <- ind.rep(i, p)
        j1 <- j[1:p]
        j2 <- j[2:(p + 1)]
        ee_per_3rd_dim <- sapply(1:(dim(y)[3]), function(idx_3rd_dim) {
            y_j2_matrix <- y[j2, , idx_3rd_dim]
            y_j1_matrix <- y[j1, , idx_3rd_dim]
            solve(X[j2, ] - X[j1, ], y_j2_matrix - y_j1_matrix)
        }, simplify = "array")
        if (dim(y)[2] == 1) {
            ee_per_3rd_dim <- array(ee_per_3rd_dim, dim = c(p, 
                dim(y)[2], dim(y)[3]))
        }
        else if (p == 1) {
            ee_per_3rd_dim <- array(ee_per_3rd_dim, dim = c(1, 
                dim(y)[2], dim(y)[3]))
        }
        if (is.null(dimnames(ee_per_3rd_dim))) {
            dimnames(ee_per_3rd_dim) <- dimnames(y)
        }
        else {
            dimnames(ee_per_3rd_dim)[[3]] <- dimnames(y)[[3]]
        }
        return(ee_per_3rd_dim)
    }
    ee <- sapply(1:r, one_i_array, simplify = "array")
    if (class(ee) == "numeric") {
        ee <- array(ee, dim = c(p, dim(y)[2], dim(y)[3], r))
        dimnames(ee) <- list(NULL, dimnames(y)[[2]], dimnames(y)[[3]], 
            NULL)
    }
    ee <- aperm(ee, perm = c(4, 1, 2, 3))
}
 --- R stacktrace ---
where 1: ee.oat(X, y)
where 2: tell.morris(x)
where 3: tell(x)
where 4: morris(model = morris.fun_matrix, factors = 20, r = 4, design = list(type = "oat", 
    levels = 5, grid.jump = 3))

 --- value of length: 2 type: logical ---
[1] FALSE FALSE
 --- function from context --- 
function (X, y) 
{
    p <- ncol(X)
    r <- nrow(X)/(p + 1)
    if (class(y) == "numeric") {
        one_i_vector <- function(i) {
            j <- ind.rep(i, p)
            j1 <- j[1:p]
            j2 <- j[2:(p + 1)]
            return(solve(X[j2, ] - X[j1, ], y[j2] - y[j1]))
        }
        ee <- vapply(1:r, one_i_vector, FUN.VALUE = numeric(p))
        ee <- t(ee)
    }
    else if (class(y) == "matrix") {
        one_i_matrix <- function(i) {
            j <- ind.rep(i, p)
            j1 <- j[1:p]
            j2 <- j[2:(p + 1)]
            return(solve(X[j2, ] - X[j1, ], y[j2, , drop = FALSE] - 
                y[j1, , drop = FALSE]))
        }
        ee <- vapply(1:r, one_i_matrix, FUN.VALUE = matrix(0, 
            nrow = p, ncol = ncol(y)))
        if (p == 1 && ncol(y) == 1) {
            ee <- array(ee, dim = c(r, 1, 1))
        }
        ee <- aperm(ee, perm = c(3, 1, 2))
    }
    else if (class(y) == "array") {
        one_i_array <- function(i) {
            j <- ind.rep(i, p)
            j1 <- j[1:p]
            j2 <- j[2:(p + 1)]
            ee_per_3rd_dim <- sapply(1:(dim(y)[3]), function(idx_3rd_dim) {
                y_j2_matrix <- y[j2, , idx_3rd_dim]
                y_j1_matrix <- y[j1, , idx_3rd_dim]
                solve(X[j2, ] - X[j1, ], y_j2_matrix - y_j1_matrix)
            }, simplify = "array")
            if (dim(y)[2] == 1) {
                ee_per_3rd_dim <- array(ee_per_3rd_dim, dim = c(p, 
                  dim(y)[2], dim(y)[3]))
            }
            else if (p == 1) {
                ee_per_3rd_dim <- array(ee_per_3rd_dim, dim = c(1, 
                  dim(y)[2], dim(y)[3]))
            }
            if (is.null(dimnames(ee_per_3rd_dim))) {
                dimnames(ee_per_3rd_dim) <- dimnames(y)
            }
            else {
                dimnames(ee_per_3rd_dim)[[3]] <- dimnames(y)[[3]]
            }
            return(ee_per_3rd_dim)
        }
        ee <- sapply(1:r, one_i_array, simplify = "array")
        if (class(ee) == "numeric") {
            ee <- array(ee, dim = c(p, dim(y)[2], dim(y)[3], 
                r))
            dimnames(ee) <- list(NULL, dimnames(y)[[2]], dimnames(y)[[3]], 
                NULL)
        }
        ee <- aperm(ee, perm = c(4, 1, 2, 3))
    }
    return(ee)
}
<bytecode: 0x6599868>
<environment: namespace:sensitivity>
 --- function search by body ---
Function ee.oat in namespace sensitivity has this body.
 ----------- END OF FAILURE REPORT -------------- 
Error in if (class(y) == "numeric") { : the condition has length > 1
Calls: morris -> tell -> tell.morris -> ee.oat
Execution halted