title: Error using dbrda function for the vegan package in R
body: <p>I am currently trying to run a dbRDA using the vegan package. 
  I used three explanatory matrices to explain one response distance matrix:</p>
  
  <p><code>full.rda &lt;- dbrda(bsim ~ genmat + envmat + spamat)</code></p>
  
  <p>The first one is a distance matrix while the last three are matrices (not data frames). I checked the dimnames attributes of each, no missing values either, overall everything seems ok... </p>
  
  <blockquote>
    <p><code>dim(bsim)</code></p>
    
    <p>[1] 380 380</p>
    
    <p><code>dim(envmat)</code></p>
    
    <p>[1] 380   6</p>
    
    <p><code>dim(spamat)</code></p>
    
    <p>[1] 380   3</p>
    
    <p><code>dim(genmat)</code></p>
    
    <p>[1] 380   2</p>
    
    <p><code>all(attr(genmat, 'dimnames')[[1]] == attr(bsim, 'dimnames')[[1]])</code></p>
    
    <p>[1] TRUE</p>
    
    <p><code>all(attr(spamat, 'dimnames')[[1]] == attr(bsim, 'dimnames')[[1]])</code></p>
    
    <p>[1] TRUE</p>
    
    <p><code>all(attr(envmat, 'dimnames')[[1]] == attr(bsim, 'dimnames')[[1]])</code></p>
    
    <p>[1] TRUE</p>
  </blockquote>
  
  <p>but for some reason here the error message I get : </p>
  
  <blockquote>
    <p><code>full.rda &lt;- dbrda(bsim ~ genmat + envmat + spamat)</code></p>
    
    <p>Error in dimnames(u) &lt;- list(dnam[[1]], c(axnam, negnam)) : 
      length of 'dimnames' [2] not equal to array extent</p>
    
    <p><code>traceback()</code></p>
    
    <p>3: ordConstrain(Y, X, Z)</p>
    
    <p>2: ordConstrained(X, d$Y, d$Z, method = "dbrda")</p>
    
    <p>1: dbrda(bsim ~ genmat + envmat + spamat)</p>
  </blockquote>
  
  <p>I've seen people got this error when they were trying to do a corrplot and use a data frame instead of a matrix but that is not the issue here.. </p>
  
  <p>Is there anyone who might have suggestions or ideas to overcome this issue ? </p>
  
  <p>I am using the version 3.5.1 of R and the version 2.5-2 of the vegan package.</p>
  
  <p>Thank you a lot! </p>